Very useful content and perspective. I was certain it was all building to the conclusion you should hire the author's growth agency to get that 2x conversion gain and then leave the funnel alone, but the ask never came!
The real thing I was thinking was that productizing the activities of a growth team would be ideal. If you could build a software product that efficiently managed the process of the growth team you could make a good value proposition. e.g. one person ($150k/year) using one tool ($100k/year) is significantly cheaper than the $650k/year he quotes.