I think I've spoke about this here previously, but I do feel YouTube radicalised me in my early 20s. In my case though it was from the left, not the right, and ack then there was no real recommendation algorithm. There was trending videos and subscriptions, but if I remember correctly the only recommended stuff was basically just related content next to videos.
Personally I don't know if the current recommendation algorithm is any worse than the subscription feed. I think we humans might actually just be drawn to more extreme or "pure" versions of our own beliefs. At least I feel this is true for myself as it's something I have to actively fight all the time.
A good example of people being drawn to more extreme versions of their own beliefs is TV news. People who watch CNN don't watch Fox News and people who watch Fox News don't watch CNN. This self-selection of media content serves to amplify political division and radicalise people because most people will only watch and read what they already agree with when they have to pick the content.
So I think there's an argument to be made here that while not perfect the YouTube recommendation algorithm might actually be better than the old way of consuming content by personal selection. And I guess the fact you were recommended something you so strongly disagree with that you wrote this post you're kind of proving what I've been thinking. This recommendation clearly didn't serve to radicalise you, but for better or worse it might have helped you understand what people you wouldn't normally interactive with actually think on some subject matter. And sometimes you had the perspective, but I find I often that's not the case.
So yeah, while YouTube sometimes recommends me crazy stuff, I no longer have a list of 50 far-left videos waiting for me when I open the site. And while I find what I'm recommended is still biased to my personal preferences, it's less biased then myself.