"Because that disagrees not only with the common sense of seeing what is happening in front of us, but also with all the other evidence I've seen"
This statement suggests you haven't looked at (m)any scientific articles. I've read dozens of scientific articles about long COVID. If you posted a reasonable rebuttal to some of these, it'd be one thing. But simply stating you've never seen any evidence? That's a statement about your own level of knowledge, not about COVID19.
Aside from that, I do look at "that idiot's Twitter feed" from time to time. Your comments mirror the things he posts downplaying COVID19. Perhaps you look at secondary sources based on his Twitter feed? Or the same sources he does? I'm not quite sure.
As an aside, I'd advise everyone to read "that idiot's Twitter feed," much as I advise everyone to read international news source, left-wing news sources, and right-wing ones. You don't need to agree with someone to read what they write.