Yeah, that part was rather tongue in cheek, I'm aware that those aren't actually grounds for impeachment. Though there's nothing subjective about Trump being incompetent or about him massively damaging the global reputation of the US - especially now that he was actually reelected, with even a plurality of the popular vote.
And by the way, earlier this year Republicans launched impeachment proceedings against Mayorkas, the Secretary of Homeland Security, on account of his failing to secure the border sufficiently - that's pretty much impeachment for incompetence, no? And that did pass the House in the end with almost all Republicans voting for it, despite all the people commenting it wasn't constitutional, though it went nowhere in the Senate.
Heh, yes, if those were grounds for impeachment, I certainly could've seen the Republicans launching the procedure against Biden, with the Dems' main counter-argument being 'well he may be bad at the job but he's still miles better than Trump'.
You say that now, but wait until we see who runs in 2028...