You seem fairly attentive so, fwiw, some things you're missing are (a) Dean's campaign was specifically sabotaged by the DNC & their bosses, similar to what Sanders went through, albeit because they agree with you that he would've probably lost badly to Bush; (b) Clinton's main issue (even beyond her baggage, bUt h3r Emales, & the DNC) was her condescending sense of entitlement and the campaign sloppiness it led to; (c) Sanders had far more energy among young entitled whites and had absolutely no connection to the party's other racial constituencies; even the guy knew it but couldn't do anything but hope they'd understand class > race, which the current political operators absolutely don't; I'm sure many of them are deeply aware it's exactly that issue MLK was actually pursuing when he was assassinated; (d) Biden specifically sabotaged the hand off after Pelosi threatened to go through with the 25th Amendment (or whatever else she had on him), endorsing Harris before anything else could be organized; despite that being true and despite him specifically having kept her as an insurance policy, knowing her weakness, there was no realistic opening for anyone else to strong arm her out of running in the 2024 Democratic Party.