Well, if we put it this way, the same could be said of Rails 6. I understand their plans of course, and that's why I expressed it as wish.
Regarding MariaDB or PostgreSQL, can you enumerate/detail the app you've seen switching? Is it the, say, 1/2% area of all the projects? 5%?
Probably, in the low one-digit percentage, there are switches toward anything. I'm somewhat skeptical any non-trivial projects undertaking this kind of change. GitLab (to mention a large one) didn't really switch, as they were supporting both.
When you install 'mysql'/'mysqld' in Debian or RHEL7+-based distros, you get MariaDB... So staying with MySQL and not "switching" to MariaDB is a lot more effort. (MariaDB is a fork of MySQL and the binaries and everything even have mysql in the name so everything just works. I'd assume there might be some divergence in newer features, but I haven't noticed anything in that regard.)
Regarding MariaDB or PostgreSQL, can you enumerate/detail the app you've seen switching? Is it the, say, 1/2% area of all the projects? 5%?
Probably, in the low one-digit percentage, there are switches toward anything. I'm somewhat skeptical any non-trivial projects undertaking this kind of change. GitLab (to mention a large one) didn't really switch, as they were supporting both.