No, not yet.
The Proton C is based on ARM, and offers some advantages over the Pro Micro and Elite C - especially better performance and more flash memory, which enables you to work with your firmware more freely if you're a power user.
However, the part of QMK that lets split keyboards work does not yet fully work with ARM. It's being worked on and the current estimate seems to be that it should be ready by Q3 2020.
In the meantime, my advice is to use an Elite C if you wish to use USB C. If you wish to upgrade to a Proton C in the future, you should consider socketing your controller with Mill Max Sockets so it can more easily be replaced.
The QMK Proton C, image courtesy of qmk.fm.