This topic seems pretty well wrapped up and has a lot of interesting perspectives, but I think I can add a fresh angle from sport psychology. As I’ve noted before in this forum, competitors in sports and games generally have an extrinsic motivation (EM; winning, awards, etc,) or intrinsic motivation (IM; self-generated satisfaction). If you are young, well equipped by nature, and have the time, you will probably go further with EM. If you are old, less well equipped, and have little time, you probably need IM to sustain an interest in go.
The OP’s opening descriptive (“fascinating”) is also my favorite word when talking about go, and it suggests IM. However, I think it is clear that the OP is primarily extrinsically motivated and probably doesn’t have the time needed to become as strong as he would like, so I agree with his self-assessment.
I see the association with “fun” as alien to my viewpoint. I find go enjoyable, but not really fun. The distinction? Reading Waiting for Godot or One Day in the Life of Ivan Denisovich can be enjoyable but they are surely not fun (though Lucky’s speech is rather funny). Go is too hard to be fun, but it’s endlessly stimulating to my thinking and curiosity, which is enjoyable. On the other hand, I did feel that distance running was fun, though seriously painful, back in the day, but that was perhaps because of the EM of camaraderie with the team and even with opponents. It also gives an IM due to the visceral feeling of increasing strength as once improves, though paradoxically it becomes increasingly painful as one gets stronger. I imagine this may happen in go too—didn’t Cho Chikun once say he hated go?
I had a rare opportunity a few weeks ago to play at the Arlington (VA) AGA club (they had about 12 boards that night!). Played a decent game against a 9k, but finally got cut to pieces due to a joseki mistake much earlier in the game, Then I got embarrassingly smashed by a 5k. This was losing in style—and it was exhilarating because it was so delightful to see all those new faces playing go.
There are so many ways to enjoy go if one really finds the game fascinating in itself: studying books; watching teaching videos, or live game video commentaries, or streamers; playing different board sizes or speeds; doing tsumego; or watching games on OGS. I may lack competitive spirit in my old age, but I don’t mind marinating in mediocrity as long as I enjoy it—and after all, it’s only a game.