This is still crazy to me that most (all?) smartwatch cannot get past ~50m WR when I can buy a basic casio for a fraction of the cost with 100m to 200m WR. But then I guess using a tactile screen underwater is pretty hard. I really don't see the Apple Watch being use has anything but a gadget for diving. edit: so the apple watch ultra has a WR of 100m. I stand corrected.
Recreational diving is regulated to 40m. The app follows the latter.
It is unlikely your Casio would be rated for recreational diving beyond the same limits either