Some companies already trying to address this issue:
Toyota/Audi - using both direct and port injection (for example new Audi EA888). Also, Toyota hasn’t announced their DI Turbo yet, probobly because of this issue.
Mazda – claims that keeping intake valve temperatures above 400C will prevent deposits on their non-turbo DI.
Personally, I would stay away from DI engines for the next few years until this issue is resolved.