Many things, too many to even remember.
Very bad SQL implementation is a good start, still bad replication support (compared to Postgres), various bugs present for too long…
https://www.sql-workbench.eu/dbms_comparison.html this comparison is a bit out of date, but explains a lot
It doesn’t, never did, never will.
I can’t believe we have to argue in 2025 about this.
The whole project 2025 is about breaking bad regulations, antitrust won’t survive. You just have to kiss the ring, and do whatever.