Did. You can't publish landing pages for products that are not even MVP on HN, IndieHackers and Product Hunt. The only one that you can is BetaList. I think my question is valid. Because if you listen to famous makers and influencers like Peter Levels, Justin Jackson and others, they use their Twitter channel as a primary source for validating idea. The others, that don't have 10K followers are in a tough position because you have to first build an audience. With what? Blog posts?