People have been blindly following whatever MSM told them at the minium since 2016.
The Orange Man™️ was their boogeyman, and through making him out to be some sort of Hitler Jr., they could simply relate anything they wanted their audience to hate to him, guilt by association on anyone and anything they don't like.
But it's definitely been going on longer than that, they just saw an opportunity in 2016 and took it all the way.