I do like not doing anything, particularly not having to do anything. Perhaps over a longer time period I would think differently, but so far I haven't felt it. However, not doing anything is a waste of time. It doesn't really give me anything and excessive wasting of time has negative consequences on life. If I were wealthy enough then I'd probably do it way more.
I don't. Although if reading qualifies as "doing something", I guess I'm almost never not doing anything, because if I don't have anything else to do, I almost always read. Of course I've always been careful to have plenty of reading material on hand; one nice thing about a smartphone is that you can carry a whole library around with you wherever you go.
In situations where I genuinely have nothing to do, not even read, I might get bored if I can't come up with something to think about, but I wouldn't say it's uncomfortable for me to not do anything. It's just a situation where it's on me to come up with something to think about.