In my experience, PostgreSQL misses just a few things compared to MySQL:

- Tables cannot be organized as a clustered index (this can be useful to control rows ordering at the storage layer).

- No builtin query cache (but I'm not sure it's very useful).

- It's easier to find hosted MySQL services like Amazon RDS Aurora and Google Cloud SQL.

- YouTube Vitess for MySQL is really great. I don't know if there is something similar for PostgreSQL.

I won't write about the endless list of PostgreSQL's advantages since it wasn't the question ;-)