Agreed, now that JSON/JSONB support is so good in postgres and MySQL, I see less and less of a reason for the NoSQL databases of yesteryear.
There was a really good post from Martin Fowler a while back that the popularity of "NoSQL" was really because it was "NoDBA" - app devs could sidestep the bottleneck of needing to get DBAs involved whenever you needed to persist an extra object field. While it's easy to abuse JSON storage in postgres, for things that are really just "opaque objects", vs. relational properties, appropriate use of JSON columns can save a ton of unnecessary overhead updating schemas.
There was a really good post from Martin Fowler a while back that the popularity of "NoSQL" was really because it was "NoDBA" - app devs could sidestep the bottleneck of needing to get DBAs involved whenever you needed to persist an extra object field. While it's easy to abuse JSON storage in postgres, for things that are really just "opaque objects", vs. relational properties, appropriate use of JSON columns can save a ton of unnecessary overhead updating schemas.