The point is to limit the damage of a key leak, not eliminate it. Limiting the scope of a compromise to a single connection rather than all communications for the past and future is an improvement.
And yeah, of course we're talking about a redesign. If we were content with the status quo why would we be here?
Sorry about that. Assumed you were trying to piggyback on the existing, to come up with a practical fix. Never entered into my mind that you were suggesting to overhaul the infrastructure. Yes, if you redesigned everything from scratch everything is possible. I will say, however, that getting rid of legacy is often harder than people think.
And yeah, of course we're talking about a redesign. If we were content with the status quo why would we be here?