The Democrats needed a reason to dump their placeholder candidate for 2024, and that convention is coming soon. Obviously they want to drop in a new candidate at the last minute with just enough time to ride home on the honeymoon glow. Debates are not usually held before the conventions.
They were always going to throw Biden under the bus, but this way they stop him being the lame duck for as long as possible while they protect their real candidate from scrutiny. Republicans counting chickens at this point are far too relaxed.
Flag: Clément Bardot