"just use postgres from your distro" is *wildly* underselling the amount of work that it takes to go from apt install postgres to having a production ready setup (backups, replica, pooling, etc). Granted, if it's a tiny database just pg-dumping might be enough, but for many that isn't going to be enough.

The one problem with using your distro's Postgres is that your upgrade routine will be dictated by a 3rd party.

And Postgres upgrades are not transparent. So you'll have a 1 or 2 hours task, every 6 to 18 months that you have only a small amount of control over when it happens. This is ok for a lot of people, and completely unthinkable for some other people.

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