"This post has a very naive understanding of online advertising" Not really. The post talks specifically about "just putting ads on", which means we're talking

"This post has a very naive understanding of online advertising" Not really. The post talks specifically about "just putting ads on", which means we're talking about something like AdSense and not the more lucrative options you mentioned which involve a sales team. The fact is, you'll need a really high amount of visitors to make any decent amount of money through AdSense - especially if you have several employees and investors who need to get their share. The post is right on the money. No doubt there are certain forms of advertising that are effective - but the point made by the post is that slapping AdSense on your startup's pages isn't going to cut it.