I reckon it takes the market power of an Apple to hold out on proprietary charging ports. Only reason they held out is 1) keep their accessory licensing revenue stream and 2) introduce friction with Android users (see iMessage). Almost no one else has the kind of market power to do that without pissing users off to their detriment.

Aside from Apple, the voluntary standards process was working. No one else was still resisting USB-C. Can you name some examples?