From the first link.
"In 2007, Jeff Bezos, then a multibillionaire and now the world’s richest man, did not pay a penny in federal income taxes. He achieved the feat again in 2011."
Bezos did it, twice. "Did not pay a penny" is tax, twice. Do you see a pattern emerging?
Did you read the question that I asked? Those were legitimate one-offs, so, no, I do not see any pattern of "consistency of non-payment of income tax", and those links refer only to federal income tax.