I love working with postgres, but this is one array where it needs a lot more love. If I deploy MongoDB it takes the whole machine and does its thing. With postgres, you have extremely minimalistic defaults, and then you have to turn a zillion knobs before it does what it should.

For beginners, it is a huge footgun, that makes people assume bad performance while evaluating. For the experienced PG admin, it is an annoiance and a time waster. Oh, the VM just gained 64GB RAM? PG will sit there and stare at it.

Apart from that, basically everyone starts with the PG guidelines or a generated template(25% for this, 25% divided by number of sessions for that). Then you keep wondering how much performance you left on the table.