I haven't tried not touching it for years to be honest. Longest period without a reboot was something between half a year and a year and it worked without a problem. Check the Arch website, breaking changes or manual interventions are very rare nowadays. There's just one thing you have to do if you start an update after a long time: make sure to update the keyring first or pacman will exit with an error. That's also mentioned in the wiki.

I installed Arch on my server because:

• I know it very well.
• The base system is tiny. Fewer packages = fewer problems. Everything else is in Podman containers anyway.
• It's very flexible. I have a customized encrypted rootfs which needs to be unlocked through SSH, not a very common thing I guess.