- scaling is non-trivial (you can't just add a node and have PostgreSQL automagically Do The Right Thing™)
- you can only have so many connections open to the database, causing issues with things such as AWS Lambda
- I don't remember if this was changed, but I got the impression a while ago that having dynamic DB users was a bit cumbersome to set up (plug PostgreSQL to AD/LDAP)
There are projects to automate the syncing of LDAP users to postgres but it would be nice if this was built-in.
However I get the impression that part of the reason these features aren't in the box is to limit scope creep in the main project.
All of these require a different architecture so expect to see newer databases push things even further.
Even Croach would be a massive branding improvement.
This is similar to how gimp is a terrible brand.
Mongo, on the other hand, has definitely always had the racist/ablist slur as the first connotation for me.
"Almost all" does sound like a bit of a surprise, but thinking back on it the only one I know for a fact I heard for the first time outside of a corrective context was my elder uncles friends who enjoyed self-depreciating jokes, usually with slurs for eastern Europeans in them. I first heard those as a child and only realized years later they were offensive. Most others, I think, I honestly have no idea when i was first exposed to them.
[0] https://en.wikipedia.org/wiki/Mongols (If it's used descriptively on Wikipedia, it's probably not considered offensive.)
My pet theory is that the database is named after a character in "Blazing Saddles", and I want to be able to store candy in it.
In the UK that would be "mong", for us Mongo is the planet Ming The Merciless is from.
There's been a lot of exciting work in this area over the last decade or so. Andy Pavlo's classes are great surveys of the latest work: https://15721.courses.cs.cmu.edu/spring2020/
CosmosDB is an example of a relational (multi paradigm properly) database with a quite different architecture vs the classic design, that's moved into production status quite rapidly.
FaunaDB and CockroachDB are moving with solid momentum too.