I disagree with the author. Although all points outlined in the article might be independently true, making a general rule out of it is not ok. Especially modern, agile marketing teams that understand the importance of testing and learning are able to produce campaigns that generate positive ROI/ROAS.

Sidenote: Co-founder of Admetrics here. We provide an experimentation solution that enables businesses to run marketing experiments on their data at pace, so we see a lot of test results on a day to day basis.