They(Apple) designed both. They gave the worse one to the public. I wish they had the forethought to realize that usb-c would become ubiquitous, and people would be calling for it to replace lightning. Now it’s just too late. They will need to eventually adopt the worse connector just bec it will make sense internally for all Apple devices to use the same charger.
USBc is not too big for phones. Lots of phones use USBc now. It's only too big for Apple phones, because Apple will never think their phones are thin enough until you can see through them.