Anything could happen. I do feel like Democrats are purposefully trying to lose. But what you said is possible too for those reasons. Because of the structure of US government, the ruling class could try to keep Biden in while also hoping for a red legislative wave. That way the bourgeois regime will still have some legitimacy as everything goes according to plan, while progressive defeats continue to happen because of the theatre of “gridlock.” Biden’s senile ass has proved to be an incredibly useful puppet for them. He’s been a successful neocon.

Even then, that strategy is still a gambit for the capitalist class. If the most hardcore MAGA Republicans achieve the proper numbers in the house and senate, then the ruling class will have essentially let the dogs off the leash. The system will just further descend into instability.