Why do you think the libs (and the Left) are failing so hard at online propaganda?

Why does it seem like, unless they take active steps to censor them, most online platforms will inevitably be dominated by right-wingers?

YouTube: despite banning and demonetizing many prominent right-wing creators, most comment sections are a right-wing shitshow.

Twitter: The moment Elon loosened the censorship it started skewing right.

Spotify: While Joe Rogan is not explicitly right-wing I think we all know that a large part of his audience is sympathetic to the right-wing nowadays.

4chan: while not universally right-wing it still obviously has a far-right edge.

I remember in the early days of the Internet, there was a lot of optimism among left-wingers. After all, surely the easy access to information would favor the "educated" Left, right? But no, the Internet has hardly led to any Left-wing domination.

Why do libs and leftists suck so hard at this? Why can't they be funny and engaging. The fact that Destiny of all people who's not even a leftist but more of an edgy centrist is considered one of the most successful left-leaning creators should be viewed as a huge failure of the Left.

It wasn't always like this. A few decades ago the leftists used to domimate the arts and young culture in general. The idea that a large amount of people under 25 would vote for the stuffy republicans used to be seen as absurd. When did they begin failing at the propaganda game?