You are missing that most services don't have high availability needs and don't need to scale.

Most projects I have worked on in my career have never seen more than a hundred concurrent users. If something goes down on Saturday, I am going to fix it on Monday.

I have worked on internal tools were I just added a postgres DB to the docker setup and that was it. 5 Minute of work and no issues at all. Sure if you have something customer facing, you need to do a bit more and setup a good backup strategy but that really isn't magic.