Because right now the US politicians feel challenged, and they are panicking to paint their competitor as a threat for everyone. This kind of political trick happens all the time.

Why does every post about China ends up about them abusing human rights, stealing etc. etc.

"Whataboutism" balances a hypocrisy when one POS is trying to tell the other POS how to behave and when confronted with facts ends up telling that we are not as bad POS as the other POS.

I do not see whataboutism as mistake/pitfalls. Considering the western media always shot/criticizing first.