Firstly, what do you mean solely responsible, secondly, groypers, pepe the frog, wojaks, incels, the proud boys, whoever was running Ron Desantis' media accounts and throwing sonnenrads behind his head in promotional videos, and many people currently working for Trump right now have roots in 4chan.
Frankly, I think you're getting a bit defensive.
[edit] Oh, I always forget about QAnon. That's like the first one I should say. The capital riot was QAnon. That's 4chan, man.