There is no such thing as an "async generator function" in the JavaScript language :) Do you mean generator functions, which Edge and Firefox both support? Or async/await?

I think people are upset because normally when someone shows a project on HN, you expect to be able to run it. It's cool that this is something you have made to test new features, but if you haven't put in the marginal effort to make it usable for most people, it is not really worth posting and the "show HN" could wait until you have time to work on your project.