But it becomes different when a wrong answer got "confirmed" by XP points. Let's don't say that XP point is nothing, it is something. Lots of learners will judge the merit of the answers base on XP points.

And indeed it seems to me that whereas it occasionally happens that what I consider to be "bad" replies (or more generally, posts) get a higher reputation than I think (but who am I to impose my pov on the community?) they would deserve, patently wrong answers get heavily downvoted - so the system may well not be perfect, but who/what is after all? (BTW: if we all were, then nobody would ever post wrong replies!) However it fundamentally works most of the time.

PS: sorry for all those parentheses. (Seriously, eh! ;-)