Are you aware - perhaps you're not - that I don't intend to vote for Trump in the primary?

No, I wasn't. That is good to hear (read), but you are still in the vast minority in your party. According to fivethirtyeight, Trump leads in primary polling at 55%. That means he beats all other contenders combined. Second place is Desantis at 14.2%. Barring something dramatic, Trump will be your nominee next year.

Biden is a corrupt old man who isn't physically or mentally up for the job of President.

I'm not sure if he's any more corrupt than any other senator with his long tenure. I tend to agree that he is too old for the job, but then so is Trump. Plus he is psychologically unfit, IMO. Romney called for some young blood, and I agree with him (one of the few things I agree with Romney about). And I wouldn't mind seeing more women toss in their hats. Tired old white guys is mostly what we get to choose from lately.

Not limited to the POTUS, either. Pelosi doesn't want to stop. McConnell doesn't want to stop. Feinstein. The list goes on. The SCOTUS is off balance in part because Ginsburg didn't step down while there was a good chance a liberal justice would be appointed to replace her. What is it about people in those positions that they don't want to give it up? They have more than enough money, and there are political calculations to be made (e.g. Ginsburg). (I wish there weren't, but I'm just being realistic.)

I quit/retired when I had enough money saved, and before I started getting crappy at my job (which is inevitable for everyone if they live long enough).

Joe Biden, however, is doing more damage to the Constitution that I ever imagined.

Could you give one or two examples? I know the tuition forgiveness is one that he champions, that has not survived judicial challenge. Is it unconstitutional? Maybe. I think that's still being argued by the lawyers/judges. Can you provide a clear-cut example of damaging the Constitution?