I think you're looking at it from a weird angle...
"Every single one" in your team agreeing on a single specific technological choice is one of the rarest things I can image! Developers argue about libraries, frameworks, programming languages, services, etc., and I think it speaks for itself if Postgres is the thing that comes closest in bridging the gap at least on one layer in the tech stack. Postgres is a "conservative" choice with a very active community and extensible ecosystem.
Also, nobody is ever making use of their technological choice to its full extent, you'd rarely know what you'll need beforehand, and it's just nice not having to add other storage engines when that one feature request steps into your life.
"Every single one" in your team agreeing on a single specific technological choice is one of the rarest things I can image! Developers argue about libraries, frameworks, programming languages, services, etc., and I think it speaks for itself if Postgres is the thing that comes closest in bridging the gap at least on one layer in the tech stack. Postgres is a "conservative" choice with a very active community and extensible ecosystem.
Also, nobody is ever making use of their technological choice to its full extent, you'd rarely know what you'll need beforehand, and it's just nice not having to add other storage engines when that one feature request steps into your life.