The article evidently is about federal taxes on income, so references to state and local income, property, or sales taxes are misleading.
With that in mind, the average federal income tax rate for individuals appears to be slightly over 10% of total income at present, with an additional Social Security + Medicare payroll tax a bit under 8%, for a total slightly below 18%, a lot less than the 31.5% stated in the article.
States with income taxes (seven have none, and two more tax only dividend and interest) probably have average rates in the neighborhood of the 5% I pay in Utah. Adding that to the federal average of 18% (and the article is about federal taxes) still gives only about 23%, and adding local income taxes (where they exist) would likely raise the average rate by no more than 2 or 3 per cent., giving an average of, say, 26%, still quite a lot lower than the 31.5% the article claims. New York, especially New York City, and California appear to squeeze a lot harder than most, but certainly are not typical.
Other taxes do add significantly to the individual tax burden, and depending on circumstances there probably are quite a few people who pay more than half of their income in some form of tax, but that would not be federal taxes, for the most part, and it would not be income based.