No there are far far more degrees of certainty available to researchers than just those. How much certainty is appropriate for which decisions is itself part of the domain of expertise here, a matter of research all on its own.

"This benefits everyone" has long been the battle cry of rentseekers and resource overexploiters. It may be technically correct in some narrow dispersed sense but come on. I benefit much more from a functioning ocean ecosystem than I do from a 0.0003% boost to the economy or whatever.