The new theory is that they came along the coast. Clovis culture arrived 13-16,000 years ago through corridor in ice sheets. But earlier sites, including these footprints, suggest that people arrived another way. These footprints are 21-23,000 years ago. I don't think there is any evidence how they got there, but the coast is plausible explanation.

My lay understanding is that the theory is that these earlier humans crossed the Bering land bridge but that they didn't proceed through a inland ice-free corridor (as there was none then). They likely traversed the pacific coast, which was not at the same position it is today and so would leave no evidence.

I have also seen discussion of sea arrivals, but they are much more hypothetical.

Also worth noting as the earlier arrival doesn't rule out the later ice-free corridor traversal as having also happens - it just means it wasn't the first people to arrive in the Americas.

It's not that different. There's just dispute over when exactly between 30kya and 11kya people first crossed.