I hope there have been some changes in the way scientists work since the 1960s.

I completely forgot about a very important point. When rejuvenation actually works, then it might also make the brain work better, younger and so on. If it is true, that great scientists do their most important work before reaching age X, then after a rejuvenation they might be able to do even more with their good as new brain + more experience. Then it would not be a matter of getting rid of holders of old ideas, but find a way to deal with people that have an unreachable time advantage, that cannot be made up. It would be good for society to keep experienced mind in work.