2016-2020: democrats stonewall Bernie, run a 2018 primary of Joe Manchin types, republicans run on an intensified red scare. He faces Trump in 2020 with the same basic material conditions Trump had, with maybe a slightly better COVID stimulus but the same basic timeline for developing a vaccine.

2020-2024: Bernie loses because nothing much changed under him and people are protesting him turning on BLM in the summer of 2020. The wing of the party treats those protestors as Bernie's equivalent of January 6th rioters. Trump inherits the same basic material conditions Biden did.

2024: Trump fumbled the economic recovery from COVID and made the same basic mistakes Biden did but worse. Democrats run a centrist because the left lost in 2020 after Bernie's turn toward centrism to win over the centrists. This Kamala Harris-equivalent, maybe Pete Buttigieg, has an election just like ours but the democrats can say they're opposed to the genocide in Gaza and want to end the war in Ukraine. They narrowly win the presidency with republican control of the house and senate.