It is tag spam (and rather rude). Just ignore it.
The term "bait thread" is supposed to mean a thread that is designed to start a contentious discussion... or maybe to trap people in some way. In my opinion this is ridiculous. Anyone can start any discussion they want, and everyone is free to choose to participate or not.
In reality, there are certain opinions that a significant number of people want to prevent being discussed or expressed.
The tag is an attempt to shut down discussion that the in-crowd doesn't approve of.
Just ignore it.