I do actually use Postgres still, despite its limitations.

I dislike their ideological opposition to query hints, partially because I've been bitten enough by the optimiser deciding in production to change the query plan to something that kills performance. If anything, I'd rather be able to pin the entire query plan! Obviously a better optimiser is ideal, but query plan changes are a big risk to app stability that are hard to mitigate. AWS Aurora for PGSQL actually has a query plan management system which helps with this.

Anyway, the difference between PG and the others doesn't make up for the licensing costs. Even in the specific cases where MSSQL does far, far better, the licensing costs still eliminate most of the benefit.