The problem I have with this conclusion is that "trust but verify" long predates AI models. People can, and have been, posting total bullshit on the internet since time immemorial. You have never _not_ needed to actually validate the things you are reading.
> LLMs are just text prediction. That's what they are.
This sort of glib talking point really doesn't pass muster, because if you showed the current state of affairs to a random developer from 2015, you would absolutely blow their damned socks off.
The difference is that often, particular things are more concretely defined. A ban on advertising might be so onerous you wouldn't even be able to 'advertise' your FOSS projects on HN.
In what way could you learn about novel commercial things in the absence of advertising? Word of mouth alone?
I'm actually convinced that "marketing", as such, can be completely orthogonal to profit altogether. Any sort of communication of a novel thing would fall under this banner, but I learn about new FOSS projects on here every day because the maintainers and developers are willing to 'advertise' them to me.