You probably won’t miss the MS security upgrades (providing you have 3rd party protection); but, you will probably miss being able to upgrade some 3rd party programs. It’s like the operating system suddenly becomes an old clunker, limping along until you take it to the junkyard.
Ah, come on... operating system running like an old clunker..really? A bit much but at least a dim future maybe...but many years in the future..heh. I’d guess that 90% would never know that a newer operating system was available if not for the massive news stories and would never need upgrading, but such if life. They all have to make money ya know...