Sure, I guess you can always find someone smarter. But really, Einstein had a particular "smartness" and existed at a certain point in time that made him notable. To say that someone sometime could come along and be better is pretty meaningless.
Just because the local maximum is not the global maximum does not imply the local maxima are meaningless.
How to best give people nutrition, love, security and education and everything they need to develop to their full potential are all tractable problems. How to manipulate human brains to enhance performance is something we learn more about every day. A guy in australia is unlocking savant abilities is some people with TMS. It's quite possible as these ideas blend with each other, a revolution in living could happen where the average person was functioning at a higher cognitive level then einstein. It may in fact be the only way we don't all kill ourselves by blowing up the planet.
(Plus, oftentimes people who are immensely smart in one respect are lacking in others, so perhaps there will always be room for, say, math savants who can do little else.)
The world has changed that drastically that fast before. It only takes one generation.
Figure out how to really educate kids to a maximal degree. Post-religion anti-indoctrination memetic inoculation. Get everyone on the planet food. No anxiety around sex. Pain medication for anyone who needed it. Smarter technology. Less people living lives of quiet desperation. If all that stuff happens, people could get smart fast.
I think another shift the scale of widespread literacy is possible, and it might push the average center of gravity above the geniuses of the 20th century. Not the minimum. Oops.
Those words all make sense in my head, but not really together. I really don't understand the anti-religious dogma, I think that there is a gradient in the beliefs of religious people and while there are definitely some reactionary elements, I don't think people who are "anti-progress" are united by religion.
Anyway, global average makes a great deal more sense, and I'd be willing to believe it'd work, but have my doubts on how fast most modern nations are willing to transform themselves into seas of highly educated citizenry. (Not to mention its hardly known at this point what the "best" education method is, so I'd imagine even such a fundamental retooling would involve lots of split testing at first ;))
Jesus Christ is maybe the son of god. Allah is God, maybe, and maybe mohommed was his prophet. Maybe you should kill Buddha on the path if you meet him. Maybe the world will change in 2012. Maybe the pope is the rock Christ built his church on. Maybe there is no God. Maybe earth has a soul and we are all parts of it as our neurons are parts of our brain. Maybe there was a virgin birth.
And then learning how to repeat any word the same way they chant "Allah" or "ohm" and get the same neurological effect.