Ok so a couple of things. I saw the current of this thought earlier but chose not to point it out because it wasn't as relevant but I think it is now.
I don't think feminists are a "protected class", certainly not in the same way black people are for one. This is because anyone of any race or sex can be a feminist. I think people are being slippery in trying to equate people disliking annoying shrill third wave militant feminists with a dislike for women in general, and that's just not the case at all. Nor is it a dislike for the ideals of equality among the sexes, either.
Now, finally, I think what you're missing here is that the multiple videos and the response they got was not, in fact, some type of specific hatred and so on, but rather a more normal commonly held belief and opinion. Basically, simply put, feminists are typically considered annoying and are disliked, so nobody needed to hate them for this video to be nominally entertaining. You know those "instant karma" videos where someone does something dumb and get what's coming to them? These are entertaining in exactly the same fashion. It's not hate as much as (yes, I'm really gonna say it XD) justice that's the origin of the entertainment value in those videos.
When someone as liberal as me, who has grown in a pretty socialist place and is in agreement with almost all progressive policy you can think of still thinks "well, these people definitely are annoying so this was pretty creative and funny all things considered" then the average reaction will be a few octaves less bothered than that. Trying to focus on it as though it's an alt-right thing specifically just completely misses the point or defines everyone to the right of communists as alt-right, which is just ridiculous.