I had laptop running Ubuntu 16.04, which was running for 2273 days without reboots or anything. It was located in safe place so not even security updates were installed during that time. And it was still completely fine after all these days (little bit over 6 years). It was finally shut down when there was electricity break, and its battery failed, and I decided that it was time to retire it.

There of course were tons of updates available then, but no one forces you to install them. and in Debian system instead of Ubuntu, there will be lot less, their release policy is much stricter.

They are still on the ship, and cannot get to land because of the lack of visas.