You just described Superman as well.If you have an actual solution to a problem, and it's for a good cause, and you aren't breaking any rules, and you know you have no conceivable way of succeeding through your currenr strategy, I don't see why the horse would get offended. Jon picked the horse because he liked him. He even told the horse that he couldn't have won if the horse hadn't carried him that far.
I can totally accept why you don't like the solution to the problem, I juat don't think it's a big deal.
But One Punch Man isn't a story about how hard training will help you succeed. The whole premise that the protagonist became thta OP by doing 100 crunches and push ups every day is seen as absurd, a joke, and probably not the real reason. At no point does the story indocate that if anyone tried to train as hard as him they would gain his power. In fact, there's a famous opponent called the human monster, who is the epitome of succeeding without any powers, and beating everyone else through sheer skill ans intelligence in combat, and even he has absolutely no chance of defeating the protagonist.
What humanizes the protagonist in that story is that even with all that power he still has little things that bother him, and he doesn't really care about all the power he has.