I'm not sufficiently interested in such lists to look up all details, but I did look up that "running as root", and it does seem possible (maybe even usual/normal, who knows) to run MariaDB as root. Postgres will simply refuse, period. That's a Pg-plus, I would say.
I don't see that that list claims that postgresql is not opensource. Which is good, because if anything, it's more open (the "PostgreSQL Licence" is practically the same as FreeBSD/MIT licenses). That's a Pg-plus, I would say.
Referential Integrity is a painful subject in mysql-land. Maybe it has improved. I'm sceptical.
But it is all really beside the point. The point is that a relatively new system (derived from a somewhat inferior system) is not going to catch up with postgres with its long-term focus on stability, reliability, and standard compliance (to name a few) any time soon, IMHO.