I believe it's both. Apple said that they'd be compliant with the EU regulations of having usb-c as a port for any cell phone with a charging port. I don't remember the exact wording, but a valid interpretation was that usb-c is not required if the device has no charging port. I believe apple is moving towards exclusively QI-charging and wireless connection. Reducing the capability of wired connections would in that case just be a way to move the users towards the planned infrastructure.

So it's both a spiteful move regarding the regulations, but also a move which reduces costs and pushes users their desired way.