I don't know if "fun" is the right word for me, but since AI coding has taken over nearly all of my individual hand coding (or augmented IDE suggestion coding), I find it much less satisfying to solve difficult problems with creative solutions. That always tickled a part of my programming brain, and I didn't realize how much I enjoyed that until I didn't do it anymore. Now, sure, I've broadened out to more systems-level thinking, but now the hard problems that I have generally aren't engineering problems, they're personnel problems, integration problems, planning/priority problems, and solving those usually means taking a deep breath and having a "conversation" with a senior manager, making an annoying business case, whatever else. There's much less satisfaction in that for me.