[Cthulhu_]

Disclaimer, I have no experience with this kind of thing. However, theoretically, less tools is better for an organization - see [0] - and if your job adverts say just "postgres" instead of "postgres, elasticsearch, tool x, tool y, tool z" etc, you don't need to find (or train) a unicorn that is up to speed on all of them.

That said, "postgres" is a very broad subject if you take all of those into consideration, if you need to specialize your search for someone who knows how to do X in PG specifically you're almost back at the same spot. (I say almost because I'm sure it's easier to learn a specialization in Postgres if you're already familiar with Postgres than it is to learn a completely new tool)

And caveat, there's a high golden hammer risk there. I'd start questioning things when needing to query JSON blobs inside a database.

[0] https://mcfunley.com/choose-boring-technology