Regurgitating the old Anybody Who Comments Contrary To My Ideas Is A Racist/Fascist trope.
Discrediting things like BLM is a way for people to convince themselves and the people around them that theyre not racist while still providing an outlet for their racist views. They may not even be aware that they are doing it.
Perhaps you are not even aware you are doing it.
More accurately, your initial instinct is to declare persona non grata anyone who comments contrary to your mindset.
Rather than discuss solutions to racism theyre initial instinct is to discredit it.
Ought not to be.
It should to be called out.