Sometimes I will go months at a time without using the gaming rig. So it doesn't make sense to have it idling; plus I don't want Windows running updates in the background (I occasionally have to go in and manually disable all of the auto-updates in the registry). It literally just has games on it and is hooked up to the TV; no keyboard, no mouse.

As for the Switch -- I love it for the reasons you just named. It really does have instantaneous boot times and most games load pretty quickly. There are a few titles with poorly optimised loading (usually Unity and UE4 titles), but that's the nature of general purpose game engines. Otherwise, you're spot on that the Switch is fast, fun, and very accessible.