@LunaDW HAHAHA! Your phrasing was spot on 'fallen into some money'. As my sociology teacher loved to repeat, luck crime or education. You basically can't escape your 'born into social class' without one of those three or a combination of.
As for China? Social mobility all but doesn't exist even in the US. Higher education amounts to indentured servitude if you make a mistake and fail at earning your 'degree'. Hell even if you do earn a degree it better be for a real career, not some art major nonsense.
As for this MC. First it's like modern world, news travels so most of the people know he went to university to become a teacher & currently is what a teacher in training (at least in others view). The recent news of him becoming principal hasn't spread.
As for cultivation & what not? It's much more reasonable to assume your weak & poor friend isn't some supreme God level expert. After all anything is a gradual process, MC simply skips shit cause he has way higher level knowledge.