The scenario you laid out is certainly plausible with Biden’s age.
I still think a obscure Democratic ticket would ‘doom them’ in 2024.
I would like to believe that votes matter, but I have lost faith in the electoral system. The "elections" will be decided by the logistics of fraud in 6 key states, just as they were in 2020.
What may hinder the Democrats is an economic bonfire that sets their factions at each other's throats. That is pretty well unavoidable at this point. There isn't now and won't be later enough loot to payoff all of the supporters, and the ones who get shorted will be the ones who start the shooting.
I am guessing that the French Revolution is a model for what we may see from 2024-2035. "History does not repeat, but it often rhymes".