Yea, when it comes to the alt-right / manosphere stuff, I don't think there's a lot of self-selection going on. The social media algorithms are largely steering boys and young men down these paths. Log out and get a fresh IP (or VPN), and take a random walk on YouTube to see for yourself. Within 10 clicks or so on recommendations, you're likely to start seeing one or two alt-right videos, and once you click on one, you're done for--90% of your recommendations will be things like "Become Alpha Male by increasing Testosterone" "Arguing with women and liberals using facts and logic!" and "Mussolini wasn't that bad!"
I can 100% agree with this. I’m a pretty liberal person (my father says a little left of Lenin), but I did grow up in the south shooting guns with family, and am still interested in firearms and related information. It’s so hard to get youtube and other things to actually believe that I’m liberal because “guns”.