The reason why a police officer spoils a whole department, while a riot doesn't spoil a peaceful protest is easily explained. One is an organized government funded body, and the other is an independent nonprofit. It makes perfect sense for an organized government funded body to protect members of it's organization by not only giving softer reprehends to it's members that would otherwise put citizens years, if not life sentences. They are held at a lower standard by law enforcement when they should be held in a higher standard.
There have been steps over the years to remove radical members of law enforcement yet we still see some amount of complacency when it comes to police brutality, and unarmed civilian homicide by cop. These are in need of being addressed and it makes perfect sense for taxpayers to demand that police departments scrutinize their members carefully if their job is to enforce laws rather than break them to fund their own departments.
You need to think bigger than organizations being left or right. Both are owned by major corporations and the public is caught up in their privatization of the federal government. You say Sorors, they say Kochs. You say MoveOn, they say Proud Boys... You say Trump, they say Biden.
It's all very binary and all of it serves to get you to conform to one political movement or the other.
Yet, people cry for term limits and do not understand how they work. If you believe only one party to be good values, policy, and competence then you effectively support a one-party system. Putting that aside, no matter what narrative you ingest and regurgitate, it seems stupid to allow Trump to remain in office because he is somehow a threat to the status quo.
He is the status quo. So is Biden. Neither deserve more than a single term if we cannot have a third option.