when to upgrade to new Mac

I have connectivity problems from time to time, email won't connect, safari won't connect to a website, email is very slow to load. If I shutdown and restart, things get much better, but I'm having to do this more and more often. My mini is late 2014 with the latest Monterey software running, 12.5.1. Also there are glitches with Microsoft office in excel and word.

Are these problems due old architecture trying to accommodate new software?