To be fair, alt-right content is present in all types of medias: short videos, but also tweets, articles, long videos, essays, etc.
The fake Facebook groups created by Russia to antagonize two local groups did not need shorts videos to succeed: https://www.npr.org/2017/11/01/561427876/how-russia-used-facebook-to-organize-two-sets-of-protesters
If you look at Twitter nowadays, the “For you” is going to be more or less what you listed above
Facebook, Twitter, even Reddit nowadays promote a certain type of content (reaction inducing), so unfortunately it’s not only shorts