`dnf upgrade` or `apt update && apt upgrade` once a month isn't so much work. If either includes a kernel upgrade then it's `reboot now` and I'm done.

But if you're doing that, it's not just sitting there, and you'd never get anywhere close to years of uptime.

I'm most cases people stress uptime too much. Developers worry about downtime during restarts and overcomplicate everything because of it. Meanwhile, my national railway reservation system has an hour of planned downtime daily and life carries on.