However, I think it's still dual-sim, not tri-sim. If you have a physical nano sim (such as from your home carrier) you cannot also have two esims active at the same time. You would have to pop out the nano sim to use two esims at the same time.

Some U.S. carriers will swap out your post-paid, physical nano sim for an esim, but I've heard it can be difficult to get the carrier to agree to do it, or they try to make it a cumbersome process (sometimes must be done in select brick-and-mortar stores, or they have to mail you something, etc).

It would be great if iPhones allowed tri-sim (home carrier PLUS two esims active at the same time). Maybe next year!