As someone who has been incredibly fortunate to be able to do pretty much whatever I want for the last 15 years I can tell you from personal experience: you can get sick and tired of pretty much anything and everything, and it happens a lot faster than you would expect (or at least a lot faster than I expected).

One of the really serious problems is that your brain generalizes, so once you get sick and tired of one thing, it's easier to get sick and tired of the next thing because your brain says, "Oh, this is kinda similar to this other thing that I already got sick and tired of."

Managing all this can be a real challenge. Not that I'm complaining, mind you, it's an incredibly nice problem to have, and I wouldn't trade it for the world (literally!) But even nice problems to have can still be real problems.