Apple has nothing to do with the SIM anyway. The SIM is provided by and provisioned by the carrier. All current Apple iPhones use nano-SIMs but other than the size of the SIM itself, there is nothing special about any carriers SIM and an iPhone. It uses the same nano-SIM as any other make and model of cell phone on the carriers network.
So the notion that a new Apple iPhone would require a change of SIM, or some mythical “special” SIM for a new iPhone is absurd on principle. You can go to any store selling SIMs off the shelf and grab one, stick it in any iPhone every made and assuming the device is not carrier unlocked, it will work just fine. Just as any other carrier unlocked cell phone using the same size SIM would.
Cricket is a supported carrier, so Cricket SIMs will continue to work just fine - Wireless carrier support and features for iPhone in the United States and Canada - Apple Support