Earlier quoted context omitted.
Curious what makes it clickbait though, I just read it and it seems like genuinely good advice when most products fail due to lack of marketing / sales rather than lack of technical know-how?
Was "Content fails to accord" really unclear? > marketing / sales Marketing != sales. The accurate title "Do marketing before build" would have got more "well obviously" than clicks.
But more to the point; selling isn't marketing, you are correct. However, at a certain level these 2 activities are nigh-on inseparable and benefit from having a coordinated approach. Regardless of where you draw that line most business owners (especially SMB) suck at marketing AND selling.