I’ve been daily driving a Fold3 since launch and while I love it and it’s the right device for me, I highly doubt they will ever catch on as the mainstream choice, regardless of display/form factor advancements.
I was the guy that carried a phone and a tablet basically everywhere for years, then used a Note9 for years which wasn’t quite big enough to replace the tablet so I went all in on the Fold3 after a couple of generations of working out he kinks with the Fold 1 and 2.
Now I’m stuck buying expensive folding phones for the rest of time because I don’t think I can ever go back to a flat device.