> If the customers of online advertising platforms ever realise that much of their ad-spend is in vain and cut their ad-spend proportionally, do you think that the internet as it is today will change?

Oh of course it will, we're already seeing the first effects. Or rather, Twitter (now X) is - they lost pretty much all major brands as advertisers and the majority of their income as advertisers realized that appearing next to Catturd, porn spammers and dropshipping scams is not a platform that yields high returns.

The only platforms still offering decent ROI are Meta and Google's search results, and the real game for online advertisers these days is influencer marketing.