Precisely. Flatpaks solve an important problem. Perfect should not be the enemy of good.
Binary compatibility is a sad story on Linux, and we cannot expect developers — many of whom work for free — to package, test, debug, and maintain releases for multiple distributions. If we want a sustainable ecosystem with diverse distributions, we must answer the compatibility question. This is a working option that solves the problem, and it comes with minor security benefits because it isolates applications not just from the system but from each other.
It’s fair to criticize a solution, but I think it’s not fair to ignore the problem and expect volunteers to just work harder.