in this case, apple display connector (adc) predates dvi, so they didn’t really have any other option for supporting an all-digital signal path to an lcd monitor, especially not one that could also power the monitor and provide usb.
this happens a lot with apple proprietary connectors. lightning predated usb-c by almost 5 years, and it was a much better connector than the existing industry standard at the time (usb micro-b). it didn’t really start to feel like a problem until many years later when usb-c started offering most of the same advantages and more.