Let's say we've got the brightest minds on the biggest problems.
They come to you with the solutions to the largest problem: nationalize the energy industry globally, convert nearly entirely to mass transit systems, dramatically decrease consumption in the global north, and convert to a state-run economy because capitalism will collapse under decreased consumption.
What now? Is that going to happen just because the smart people are working on the tough problems? Of course not. The real biggest problems are not actually a matter of smart people knowing the solutions, but of competing powers (that are much stronger than you as an individual), propaganda, exploitation and human subjugation that prevent balancing against those powers, war, etc.
Worse, while it may seem like a good idea to have the wonks working on the biggest problems, consider the immediate precursor: who decides on what the biggest problems are? Right now, that will end up being heavily influenced by the moneyed interests that create the biggest problem. You'll stick entire generations of the biggest and most clever nerds on making better batteries and electric cars, but ever-growing consumption will make all of that moot and the descent into collapsing ecosystems and agriculture all the more inevitable because they were focused on a lack of tech (stuff to sell / consume) being the biggest problem rather than questioning core structures (an imposed economic requirement that consumption always increase lest we all go hungry and die).