Oh stop being so high and mighty. Chemophobia! Really? H2O is probably the most widely known chemical formula - go out and ask twenty random people what it is and you will get 19 answers for water. Ask those same 19 people what dihydrogen monoxide is at 8am on a Tuesday when they are trying to get kids dressed and out the door, then say "contaminated" and the answer will be "I don't know but it sounds nasty" Yes it's…
You're asserting that, simply because people are capable of holding down jobs, owning homes and producing kids, that the general stigmatization of sciences and pervasive anti-intellectualism is insignificant because people can still intuit what constitutes as good and bad education and policy? This is absurd. Just because people may be capable of functioning in the real world without access to scientific knowledge does not meant that we shouldn't pursue the proliferation of such knowledge. Whether people need to know what Dihydrogen Monoxide is is largely inconsequential. Insofar as scientific knowledge is, unto itself, a good thing, policymakers should strive to promote it, regardless of its practical implications.
It's preferable to be an informed functioning citizen than an uninformed functioning citizen, despite the fact that they are both capable of doing their jobs every day.
As an aside, "Half of the population is below average intelligence" is false. Half of the population is below the median intelligence.