Yes LeP, thats accurate but not complete. The problem now is that FPC (main) has been allowed to evolve to far from FPC322 that its very hard to compare the two. It is, in effect, a new product. Maybe we need new branch, fpc-ng, subject to some public testing and release as, just that, a new Pascal Compiler ?
Ok, some jest included

Davo
I didn't want to delve into the specific development difficulties of FPC,
but the problem here seems to be that there's no concrete "governance" of the project and it's being moved haphazardly according to individual needs.
The fact that the latest official stable version still has problems with "generics" (and has been for 5 years now) is illustrative.
If a core developer got, say, $5k USD for the work, would inline variables be implemented then?
I'm just curious whether the real limitation is technical, ideological, or simply time - and if money would change anything.
If someone made a proper, clean implementation of inline variables, would there be any chance of merging it into trunk?
Even if, as @FIbonacci says, someone were paid to make a new implementation (and it would be yet another one), on which version would it be applied, and what would be the release time and maintenance cycle?
Always thinking of a SINGLE FPC, because otherwise it would be enough to create your own repo and develop independently.
P.S.: many have claimed that the trunk version isn't ready for release and production, so what's the point of all the effort put into making changes to this "version"? I mean, is FPC still a viable product for building something reliable, or is it just for hobbyists?