Many if not all tubeless ready rims will have tiny bumps just on the inside of the bead seat that help keep the tire bead in place. It does make it a little bit harder to remove the tires. But not that much. I can still do mine by pushing it off with my thumbs. Or you can simply use a pair of channel locks with padded jaws or buy the correct pliers.

I don't think you'll find that you can assuredly find that any claimed loose fitting tire is anything by unique to the person touting them as loose. Your experience with that same tire will just depend on how well you understand what you have to do to get that tire loose.