So far, that seems like EXACTLY what MS is doing for 2024. Remember that, given MS’s behemoth size, there are licensing issues involved, but, apparently that’s been resolved.
As was written above, apparently MS is working with AIG to build a library of low res planes to be streamed in 2024 (along the lines of AIG/FSTL/Just Flight AI Products). These won’t, currently, be linked to 3P aircraft, other than the hope they properly model match to the right plane, even if it looks “different” for the other users, but, it’s something. And, as you noted, livery support I imagine will be a huge issue. I just hope they’ve at least finally fixed the white reg number square problem that’s been with us for 4 years.
And it’s possible the option could be extended to 3P vendors to have them send MS low res models of their planes, maybe as part of the Marketplace submittal process, and they could be used as well, and maybe at least the standard liveries that are delivered with those planes could be supported. And 3P liveries could be supported, too, assuming there’s a way to create them that works, and if you know you’re going to be flying with a friend, you could download their livery and it might work (the current generic planes have issues using the standard liveries, as I imagine their mapping is different). But, those low res models are not an insignificant amount of work.
All this discussion is the stuff of “Wishlist”