I think the key part is less that and more the way of phrasing it. So you're encouraged to ask non-technical questions how they're supposed to be better than th

I think the key part is less that and more the way of phrasing it. So you're encouraged to ask non-technical questions how they're supposed to be better than the competition but not allowed to say "but Google dominates that space, doesn't it?" to imply they don't necessarily need to exist. (though the author also says "I think your UI is not good" is 'constructive' feedback, so they don't think you have to be nice!) I think there's a point to that especially if it's a business you don't know and you're not a VC or angel, but I also think there's a surprisingly large number of entrepreneurs out there who are smart enough to live off ramen and program something complex like a search engine who do have a massive blind spot about routes to market or the complexity required for the software to actually be viable rather than just minimum. Sometimes the blunt approach "doesn't the network effect of $dominantplayer create a massive lockin" is more helpful than a general "so how are you going to get customers?" which is easy to answer with a generic "sales/marketing/referrals/affiliates". The entrepreneur ought to be able to give a more interesting answer to the first question, and if they aren't able to they're going to need to figure it out...