I don't know why this is attractive to people - i have yet to meet this kind of guy in real life. the closest i can come is the overachiever who actually works super hard, but just acts like it doesnt mean much, i appreciate this kind of guy for his hard work anyway
There's also just people who have unexpected skill and/or talent, in an area that you wouldn't expect.
What doesn't happen in real life (to my knowledge) is the manga trope of the (shounen) protagonist who's amazing at everything (more or less) but normally just can't be bothered; that much falls firmly into the category of fiction. Of course, the flip side is, it's interesting in a story partly because it's so unlikely.
Then again, there probably are a few people in the world who at least come off that way, I suppose, out of 8 billion people...
Well, thanks to the Slice of Life genre, all of us are protagonist material anyway, right? :'D
Is it confusing the happiness from exceeding expectations or does the character just generally have a good face which gets even better when he looks serious...i strongly believe it is the latter
Wait, good face as in good-looking, or as in well-thought-of? :/
On the other hand, there is a nice dilemma in that if you do nothing and work only when it counts, you'll get abused all the time, and if you work hard all the time, you'll get overused and insulted for not caring about yourself aaaahh what should one do..? [not really]
Which is why you should take a third option and be reincarnated into an isekai [not really].
uwu