[PsYcNeT]

Personally I believe we are spawning more Newtons and Einsteins all of the time, the issue is, is that the science itself has become so complex that geniuses do not have the earth-shaking magnitude they once did, as it's humans that are limited, rather than the science.

Think of it like a game of Civilization. Each "Great Scientist" has a +500 (or whatever) to the total technology of your civ, regardless of the era they are born in. Up until ~1960ish, the amount of "points" needed to discover a new technology were below 500, so all that was required was a single "Great Scientist". After 1970 however, the required technology "points" has risen dramatically, to where we are today, where it takes dozens or more "Great Scientist"s to discover one new technology.

Don't blame limitations of science, blame the limitations of humans.