Software also looks at future dates, so the problem is actually going to start to occur much sooner. The kernel will be fine, it’s all the other random software floating out there that you should worry about. A lot of in-house calendar and booking software is probably going to start to blow up soon.
There are likely lots of improvements that can be made under the hood. I’m willing to bet that it depends on several aging libraries that could probably be swapped out for something better.