I called it good at ascension 2 and uninstalled, doesn’t the novelty and enjoyment wear off long before you’d hit ascension 20? I guess this is maybe why I’ve never really been an expert at anything just pretty good.
I don't think it's a problem at all that you didn't enjoy it after A2. Some folks do (like Jorbs or your comment's parent) and some don't.
If your line of questioning was more along the lines of why it didn't wear off, I can give my own anecdote. I found that the increase of difficulty makes the game more interesting to think about because you have to be much more methodical in how you craft your deck and play it. There are a lot of variables to manage and account for too.
I feel like after 12 or so hours of chess I'd figure out how to not hang pieces. From there, how to find the best moves is just a question of dedicating energy into finding them in game.
I'm not sure why anyone plays more than 100 or so hours of chess. Doesn't it get boring?
Don’t get me wrong. I’m impressed with people doing it, but I don’t think I can.