Sounds like a good use case. At the risk of someone shooting me here, for user profile metadata I’ve often used an EAV table, and it seems to have worked quite well :running:
Perhaps Oracle still put their own engineers onto MySQL work, and it was thought MySQL was getting better/more contributions than MariaDB? I doubt Facebook and YouTube/Google would see Oracle in anti-corporate terms (as I normally would) since they themselves are large corporates. So it could be a mindset thing, just as much as a contributions thing.
For what it’s worth, I do support the existence of Maria, but I don’t know much about it. Has it kept pace with MySQL developments? Is it as well tested at high load? What big deployments can it boast? I might try it one day…
There is a list of the bottom of the MariaDB page, it includes Wikipedia, that’s pretty big
For an even better fork of MySQL, there is always Percona.
It has a few things that are currently part of the enterprise offering of MySQL and the configure that comes with it is a lot stricter than the MySQL configure that come with most of the Linux package managers (exceeding varchar limits result in an error rather than a warning + truncation)
All in all though, there are far too many gotchas in MySQL that make it worth using for me, but, if I was forced to use MySQL on a project, migrating to Percona is a quick win.
Speaking about testing of the forks, you also have to remember that Oracle has removed the test suite from the CE source code