Capitalism is an inherently unstable system due to the contradictions that define it. Scapegoats are necessary to prevent working class from rising up, and economic conditions in the US have gotten so bad that most people no longer care about sustaining the status quo. So I don’t think the current rise of fascism could have been prevented without a socialist alternative.

Also Biden had already changed the geopolitical landscape when he openly funded an (even domestically) deeply unpopular genocide.