Galera kinda improved the MYSQL replication story for certain specific use cases, at the expense of (a lot of) extra complexity and way more foot-guns. I couldn't recommend galera even when the use case matches up. It took us years to get it operating relatively safely, and that was after a heap of near-misses with customer data. (Yeah, a bunch of us thought it was folly to use it but we weren't decision makers at the time)
Even back then, I found that mysql was faster for “select * from table where primary_key = 42”, but with even the slightest complication (joins, functional queries, subqueries), postgres pulled ahead.
I guess a huge percentage of SQL queries are really just key-value lookups though, so I can’t blame people for using mysql too much (this was before memcached, let alone redis et al)
Postgres also had a reputation for being correct but slower. The perf differential disappeared a) as postgres got faster and b) mysql got more reliable/robust.