It is pretty unfortunate that so many people used "PostgreSQL" and "Postgres" in their module name and DBD::Pg didn't, so it gets ranked lower for those queries

It is pretty unfortunate that so many people used "PostgreSQL" and "Postgres" in their module name and DBD::Pg didn't, so it gets ranked lower for those queries. But ranking is a hard problem when there is no curation. The MetaCPAN team does want to improve this if possible. As for DBI, it's definitely in the "stable" category and isn't trying to keep up with anything; the DBD::Pg driver though was last updated this month.