Most major US carriers, and many worldwide, have eSIM support, and iPhones have supported them since 2018, including the ability to use two SIMs at once. Up until the iPhone 13, that meant one eSIM and one physical SIM; the iPhone 13 family introduced the ability to use two eSIMs at the same time. Removing the physical SIM — and the hole in the case it requires — is the next logical step. At least for Apple, and at least in the US — the iPhone 14 still has a SIM tray everywhere else.