Earlier quoted context omitted.
This is effectively a straw-man. Treating advertising a way to connect suppliers with those with a need is a common, benign interpretation of what it is, but that view rests on assumptions of trust or informational parity between buyers and sellers. i.e. the sellers have to be meeting genuine needs, or the buyers have to have the information necessary to make good determinations. I don't see why we should assume that…
"genuine demand" is a true scotsman fallacy waiting to happen. Purchases are revealed preferences. That people have incoherent preferences doesn't mean you get to pontificate about what they should have.
I also don't see any mention of whether people's preferences are coherent or not.
I didn't use the words 'genuine demand', but I did talk about genuine need. This isn't a true Scotsman fallacy because I am talking about the buyers ability to get their needs met, and not debating what qualifies as a genuine need - which is as you say, a revealed preference.