I don't think processors are as close to offsetting the rendering disadvantage as you think. Servers get more powerful at the same time, so I suspect the faster strategy will continue to be server-side.
Is there potential that clients will become 'close-enough'? Maybe, but I doubt the gap will ever be fully bridged.
Is there potential that clients will become 'close-enough'? Maybe, but I doubt the gap will ever be fully bridged.