First thing I thought when I started reading the post. Thanks for pointing this out.
“....you can’t directly add marginal tax rates.”
Actually, you can, but what you get is the total marginal tax rate, not the average rate paid on all your income.
Saying that health insurance is a tax is like saying homeowner’s insurance or auto insurance is a tax. Presumably no rational person is going to go completely without at least some minimal amount of coverage. It’s certainly true that government drives up the cost of health insurance: that is, the tax exclusion encourages much more comprehensive coverage than one would observe in a completely free market. Thus, I could buy that perhaps one third of insurance coverage is a tax/regulatory burden, but not the entire amount.