Why do people comment like this “ dhnvtgjjygbb”?

They are just Point Gaming just to get the 2 Points Unfortunately there is not much we can do about it but just Report the Answers and Ignore them

to make us feel bad - and it's not people doing it, but spambots

There have been many other questions about this already. Return of the spam bots (last attack was last spring). This attack became really noticeable on 12/28. Those posts are from spam bots. They are not being posted by people. They are automated. Report them. Mostly report the gibberish answers of misc letters. The accounts are attempting to gain points in order to post more Chinese language spam questions, even though we don't see those questions in the categories because the spam filter is catching them.