I agree with most of your points except with one about socialists being unelectable - I believe that Bernie would have moped the floor with Trump in 2016, and even more so in 2020. First woman president had a nice ring to it, but Hillary performed terribly, and with her being basicially an aristocrat of the establishment, lots of people hated her from the get go. They shanked Bernie so their corporate overlord donors wouldn't get pissy, and voters treated that as betrayal. After very solid 8 years of Obama it get like Dems had this victory in their pocket regardless of what they do, and they commited to proving that hunch wrong. That's at least the vibes I got from watching the elections from Europe, I did hear that Obama wasn't as popular as he seemed to be.