The good thing about reaction videos is you don't have to watch them ;-)
I get your point Gaijin but i find the word despise here a litlte bit harsh. I watched some very good ones and enjoyed watching the people react to something and giving their 2 cents opinion about it. Mostly i find their opinion bonkers, but who am i to judge? There were also some videos which gave me a better insight by listening to the thoughts of other people and i'm glad to have watched them.
One example would be the reaction of the "writer" who reacted to The Hunt and i enjoyed listening to his thoughts, how he reacts to the unfolding story of that song. There was nothing real new to me, but i had to smile as he described who it impacts him and i could relate to that. I see it as a sharing thing but i also noticed, that many people just think they can make a reaction channel to get attention and those feel not authentic.