It goes something like this:
- someone gets offended from clips, or watches the whole thing but dislikes bits they feel can taken out of context
- they say it is hateful
- everyone who listens to them takes the judgement and runs with it. No need to subject yourself to hateful content when you already know it is
- the judgement spreads, and people wanting to feel important add their own (uninformed) thoughts, which are just exaggerations of the original
- enough people say it that it becomes a foregone conclusion, and anyone who speaks up in opposition obviously only does so because they are anti-X, bigoted and hateful themselves, and so their opinions dont matter
It is basically how all stereotypes spread, with an added hint of malice thrown on top to be extra divisive. In a world of things like "anti-racism" where you must parrot the orthodoxy loudly and often, this is the natural course of things.
Culturally, I think "celebrification" is to blame for the intensity. We have spent so long worshipping celebrities, and celebrity status, that social media gave us the added shot of each of us being our own mini-celebrities. Being liked and mentioned has become a form of self fulfillment for some people, and the easiest way to do that is parrot every bandwagon you can find.