In theory the protocol could be changed to Can, BUT that would involve a lot of programming on the software of the engine ecu. You would have to rewrite all of the diagnostic software which is part of it. In practice the answer is no.
For diagnostic purposes only you could use VCDS, which is a little bit faster than EOBD/OBD2 as long as you only request 1 measurement block (with 4 values).
You can speed up the EOBD/OBD2 communication by limiting the number of pids you request.