* In that link, V11 is not the version of Postgres, it's the version of the test...

   * In that link, V11 is not the version of Postgres, it's the version of the test. Scroll down to DB Version.
   * Lots of versions are tested, but 9.2.1 is the only version I see on the same hardware that the top MariaDB versions are tested against. The others are on much weaker hardware.
   * Postgres 9.2.1 is 12 years old.

This site is not a good like-for-like comparison.