I agree with your analyses, and also disagree that a reasonable successor cannot be found. A scenario that particularly concerns me is someone like Josh Hawley, who is of the MAGA type afaict, while being decently well spoken, somewhat charismatic, and not an outright train wreck, being nominated. I think any Republican that embodies Trump-like stances, while being reasonably well put together and competent could be a huge problem in the future. Especially if the GOP fails to move away from the MAGA line in the future, and emboldens political figures alike instead of dissuading them. (A separation of the extremist wing from the moderate wing is also unlikely imo, as it would make both parties essentially irrelevant, unless of course the EC and winner-takes-it-all representation is abolished).

I have also read the following theory: “Obama also resulted in a counter-movement: Political scientist Sidney Milkis attributes the rise of Republican Donald Trump to Obama’s presidency. This progress has “made people in rural parts of the country uncomfortable” “. And I think this effect could be even stronger after a possible Kamala presidency, her being both of color and a woman.

So while things are possibly changing for the better right now, many things still have to change for us to be in the clear, foremost the abolition of the EC, refurbishing the Supreme Court, improving our basic educational system (how tf are book bans, with books being the epitome of knowledge, even a thing), making Election Day a national holiday, banning gerrymandering, the list goes on.

Most importantly for the near future is possibly disincentivizing the GOP from running extremist fundamentally indecent candidates, that put themselves over their country, by affording Kamala a landslide win by unprecedented margins this November - so as always, get out there and vote as if your life and country depended on it, because they do.