sure but most frequent/core contributors for Linux (kernel) and most big Distros are payed by some company with commercial interest which mostly doesn't involve spending time on maintaining any of this old architectures

sure some are also payed by a foundation. Which is also payed by companies but with a degree of decoupling of influence.

and some pay them self, e.g. fully voluntary work, but most dev can't afford to do so on a long term, high time commitment manner. So a lot of major changes and contributions end up coming from people directly or indirectly "payed" by some company.

and that's pretty common across most "older, larger, sustainable and still developed OSS"