I usually refer to this distinction as "tall" vs. "wide" problems. Tall problems require having at least one exceptional or specialized person to solve it, whereas wide problems can be cleared by most generalist problem-solvers. The time required to solve wide problems is simply one of aggregate bandwidth.

Unfortunately, I think society has a ton of people who can solve super tall problems working on super wide problems, because the largest (and most well-funded) organizations have the widest problems. In some cases they have super tall problems too, but past a certain size the lights stay on by solving the wide problems.