The author does say double digit equity. Not sure where you got 0.1 to 2% from.
You can browse startup boards and generally you'll get 0.1% to 2% equity of the company for being a "founding engineer".
It seems to me like the author is arguing that the you don't need a CTO, you need a technical co-founder, AKA a founding engineer, and that they should be given double-digit equity. Am I reading this wrong?