I realize some think it’s nitpicking, but just to clarify for readers, since an “a” can look like an “s” at quick glance:
What’s sometimes casually called “aRGB” (but isn’t called that in software) is really “Adobe RGB (1998)” or just “Adobe RGB.” It’s a larger color space than sRGB.
Nothing wrong with nitpicking 
To which end I have edited my original post, replacing instances of ‘aRGB’ with ‘Adobe RGB’.
Have you ever heard about ROMM RGB?
It’s the official “ISO22028-2_ROMM-RGB.icc” profile we call "ProPhoto RGB*.
Yes but it’s irrelevant for PL users, since PL’s working space is the smaller space of Adobe RGB.
It’s also worth commenting that the fact that PL can’t work with ProPhoto is a deal breaker for many users. I know this because they have told me so. I can’t / don’t see DxO caring though.
I don’t recall seeing a feature request for this but perhaps there is. If so you can vote for it and comment so your voice is heard.
Just search for the terms “working color space” and you’ll find what you’re looking for:
(See also the linked topics at the top of the second one above.)
Here’s a response from DxO Staff:
That was 2019, it’s now 2022, hence I say again, I can’t / don’t see DxO caring. Would @CaptainPO care to correct my cynicism?
I would say DxO cares but we are (most of the time) impatient and we do not know what DxO has in its hat because they have to protect their work from the competitors.
Of course a more open roadmap would be welcome.
But imagine if they announce a thing and miss the announced release date… all the comments… No thanks, there are already too many negativity for things that are not announced. I would do exactly the way they do: work in silence, slowly but surely, to deliver a better software day after day.
Now, hopefully your wishes are high in DxO’s long todo list 
The Question is short but the technical challenges and hurdles to be overcome to deliver are great.
You talk about a change in the core of the raw to pixel(RGB) programming/algorithm.
it’s like hé we need teo extra digit’s , milenium, it’s only a change between 99 and 1999 sounds easy but it was a dreadfull job for all software engineers.
I think dxo software development need to build a hole new “spine” in the raw to RGB conversion and preview engine and reconnect all other tools, bells and whistles around it.
Not an easy task and if they do the raw to RGB demosiacing Less Good then the old version in conversion quality the world is too small. Keep in mind it’s not Adobe in resources.
I am not an software developer but i am imaging that on this large changes lots of time is “wasted” on technicalmeatings in order to map out the playfield and set the markers of specs. Before you start spending money and time in coding you have to be damn sure your efforts arn’t run over by progress of time. (like building your new house for two parents and 1 kid and somewhere in the build the second is popping out…sort off) 
Hey, everyone else can do wider and selectable colour spaces and DxO should be able to do it too. DPL is the only serious photo app (I use) without it. This needs to change and I guess that it will. I’d not hold my breath though.
However, one can also expect a company that offers award-winning software to
Many points such as softproof, user interface, alignment of software add-ons (Nik), differences in Windows and Mac versions, DAM have been criticised for a long time, but have been forgotten somewhere or not actively managed.
This also leads to posts being “dug up” again and again over the years, but sometimes not commented on by DXO.
And not only the DXO forum administrators, who do a good job, should post here, but also the marketing team or the development management. With all the forum members who invest a lot of time and sweat here, at least that would be a nice gesture.
Guenterm
A.D. 2022
Yes.
Yes. (i think)
I expect too.
I only wrote that even if they will answer the feature request it still is a timeconsuming task.
That they need to get it more yesterday then tomorrow we agree on. Aldoh i am in my workflow happy enough with AdobeRGB.
Other customers need it and if they want to compete with the others dxo needs to adres to that. Point.
Yes, I understand that.
As I have already noted, I know people have abandoned PL because of this limitation. Not even DeepPrime is enough to entice them to use it.
It would be nice if DXO at least recognized it as an issue! This is an important issue!!!
I’m curious to view the print, that shows any advantage when using a larger colour space than AdobeRGB. Or the monitor that shows a relevant difference.
Or the monitor that shows the relevance of 30bits colour.
I still prefer wet chemical prints (of course generated by laser lighting nowadays) over many inkjet prints. Although their colour space is sRGB at best.
I don’t have the skills to produce such a print but I am convinced that there are people who can do so. Having the raw data mapped to the largest possible colour space (e.g. ProPhoto) as part of the initial RAW processing and then the ability to control how the resultant colours in that space are remapped to the smaller spaces of your monitor and the paper you are printing on means you have greater control of the end result, giving a subtlety to the output that otherwise would be missing. A bit like listening to a CD through a carefully set up high end hifi system vs hearing it on a perfectly adequate but less finely tuned system.
I’m not sure.
The bigger the difference in color space the bigger the differences in the end,smaller,color space.
The bigger the working color space, the bigger are the correcting steps with equal bit depth.
George
simple – get a good monitor and printer 
Hardware and stuff set apart, it depends on the subject if you profit of a wide(r) colour space. Going from sRGB to AdobeRGB is ‘easier’ to notice & realize than beyond.
While ‘my’ photobook provider mostly wants sRGB files to work with, I’m not sure about the wet prints’ colour range limitation.
Well, probably you can download the printer colour space of your photobook provider. If you have a profile viewer, you can compare it with sRGB and Adobe RGB. I don’t know if a profile viewer can be downloaded from the internet. When I worked as an R&D scientist for printing systems, I had the tooling to load multiple colour spaces in a viewer and compare them in 3D. The weakness of sRGB is in bright green colours. For the rest the difference with AdobeRGB is real, but rarely relevant. Bright green colours are also the weak point of pigment based inkjet inks. If you don’t have an specific green ink, it will be difficult to produce bright green hues because the cyan pigment is too “blue”. Dye based cyan inks are better at this point, but suffer from a worse longevity.
Of course, if you have a good monitor (my Eizo shows 99% of the AdobeRGB colour space), you can see the difference in SOME files if you do a soft proofing in e.g. Photoshop with an image that was edited in AdobeRGB and now shown in a simulated sRGB space. But definitely not always.
There are good reasons not to edit in wide-gamut spaces, because they contain many colours that do not exist in the real world, and because only a small part of the available colour space will be used. So you throw away a lot of the available grey levels/colour. Not a big deal as long as you edit 48bit images, but not a good idea if you edit e.g. a jpg with only 24bit colour depth. So you better remap to e.g. AdobeRGB to do your editing, soon after RAW conversion.
I don’t think a great image will be discarded if it is “only” in sRGB space. Nor do I think that anyone will view a mediocre image in ProPhoto and say: Wow, that color space! I think that e.g. the viewing conditions of the print (lighting) have a much greater effect than the print colour space, if of course a certain “lowest acceptance level” is met.