What techniques do bad faith users use online to overwhelm other users in online discussion and arguments?

One I see people use frequently and I’m not sure they realize it’s a bad argument is the fallacy of relative privation.

“X is bad. We should do something to fix X.”

“Y is so much worse. I can’t believe you want to fix X when we need to fix Y.”

Both X and Y can be bad and need to be fixed. Fixing one doesn’t preclude fixing the other.

An alternate form of this is:

“A is bad”

“B is worse, so A is fine.”