Why does everyone run ancient Postgres versions?

I've used postgresql in most of my previous jobs, but using mariadb in my current one, and I must say it's a joy to administer.

The replication and high availability that mariadb offers is rock solid, and much more advanced than what postgresql has to offer. It works out of the box, no plugins or third party shenanigans needed, and there is "one obvious way" to do it. Not a dozen options like in the postgresql ecosystem, each with it's own quirks and drawbacks.

Also, upgrades are a dream. I did 4 major long term stable release upgrades so far and everything was fully automatic and smooth sailing all around.

All of that with about 10 seconds downtime only for each upgrade, despite being a chunky 6TB database, thanks to the user friendly replication process.

I respect postgresql a lot, but mariadb allows me to sleep much better at night thanks to replication, smooth upgrades and no VACUUM to worry about.