Yea I don't know about BLM protests but cops have vanished from enforcing traffic laws where I am.

I would say someone blows a red light at least 50% of the time at a red light.

There might just not be enough cops now though demographically. That would be my guess. The same way there aren't enough nurses.

The protests are a red herring. It's the cops not wanting to be charged with murder so they just make less traffic stops.

I don’t think they were afraid of being charged with murder in the first place. Qualified immunity for police is quite strongly backed.