The issue with the PC tablet form factor, in my opinion, is that it's extremely limiting so long as you're trying to keep the device reasonably light and portable. It's also awkward at sizes larger than ~13". If I think about a tabletified form of a 16" M4 Max MBP for example, it'd be so clunky (including kickstand an all that) that I'd question the usefulness of it being a tablet. A 13" MacPad Air would probably be the upper limit.