It's annoying that she put this on Instagram where there's no scrobble function, and she then spends so much time leading up to it.

For those not willing to sit around listening to off-the-cuff meandering, AOC's points:

• Ohio requires political parties to submit their candidates' names before the Democratic convention. If the convention is contested, Democrats likely won't be able to vote there effectively.
• AOC says that swing states might have enough legal ambiguity in the electoral code that Republicans can challenge any voting results, and then let it escalate to the Supreme Court who can throw out the Democratic result.
• Democrats are divided on who would be the replacement candidate, with many of the people calling for Biden to step down opposing Harris as well.
• The Biden/Harris campaign has $100M of campaign funding that will not be able to be transferred to another ticket. (Maybe it can be transferred to Harris? She mumbles a bit there).
• Anecdotally, when AOC sat "in rooms with those people" that call for Biden to step down, they didn't seem to have a proposed game plan for any sort of replacement. This includes lawyers who ought to know whether this creates legal trouble and people in the legislature.
• There is a risk that if the Democratic convention is contested, it won't be concluded before the deadline to submit the ticket in more states, which is two days after the scheduled end.
• There are no candidates that poll way better than Biden.
• Many mail-in votes can already be made in September or October. A new candidate would have to have a succesful campaign by that time.
• Biden is systematically underestimated (by Democrats and fianciers?) in his ability to rally 'demographics typically not cared for'.
• Biden does great with elderly people, which may not transfer to other Democrats.
• Democrats opposing Biden seem to be mostly concerned about big donors, not popular support.
• Democratic party members speaking anonymously to the press is both strategically stupid and undemocratic. They should have either spoken out publicly or kept it behind closed doors. The fact that they did may be why Biden is polling so bad.
• Biden gets energized from having people around him, which was not the case for the debate with Trump.

My personal opinions:

• With regards to Ohio, betting websites put the Republicans at 95% chance of winning the state, and Biden appears to have been trailing by 10 percentage points even before the debate. Losing Ohio only matters if you would have won Ohio with Biden, and that's questionable.
• With regards to the Supreme court handing the election to Trump based on a bullshit legal ruling, it seems like AOC is making the dangerous and questionable assumption that the Supreme Court cares about the law, and that the outcome of these legal challenges will depend on technicalities rather than on whether they think they can practically succeed at the coup.
• With regards to the $100M war chest, this seems to be cancelled out by her argument that Democrats opposing Trump are mostly concerned about donors. In 2020, Biden's election got $1 billion in funding while on May 9th, Biden had raked in $170M according to this website. So with upwards of $700M of donations left to collect, a 14% decrease in donations would mean Biden has less money to work with than other candidates.
• With regards to other candidates not doing much better, it seems impressive that they are polling better than Biden even with Biden running a massive election campaign and having spent a hundred million dollars in ads already. I would expect the gap to widen if those other candidates actually start trying to win the election as much as Biden is.
• With regards to the votes in September and October, with regards to the elderly and demographics typically not cared for and popular support, these all seem to be cancelled out by the polls.
• With regards to the Democrat backchannels, the damage is done. It's fair that she's mad about it, but it doesn't affect future decisions.
• With regards to Biden's energy, either this doesn't explain the Zelensky-Putin gaffe, or it's kind of irrelevant. Biden won't be sitting in the oval office with an audience to work off of.

So from everything AOC says, all that seems reasonable to me is (1) the observation that there is no good Democratic alternative plan, (2) the worry that the convention might run long so the alternative candidate can't appear on the ticket, (3) the possibility that a succesful Republican coup is significantly more likely with a candidate that might provide loopholes for the Supreme Court to work off of than with Biden, and (4) the possibility of losing Ohio if Biden would otherwise have won it.

However, even here, the parts of the alternative plan she is most worried about seems to be the legal trouble, which she seems most worried about only if the Democrats aren't on time with selecting a candidate. It seems to me that if only the Democrats are able to rally behind a new candidate before the Ohio deadline two days before the convention, none of her concerns apply more to the new candidate than to Biden. If it happens after the Ohio deadline, it only matters if there is a technicality that disqualifies the new candidate and Biden would otherwise have won Ohio and that technicality determines whether a coup succesfully occurs.