None of this is actually needed to get validation.

Would me having domain email routing somehow make it more legit? No it wouldn’t, I’ve now gotten validation that people like the idea without doing any of that, which is the exact advice that y combinator gives, yet is never followed in HN comments

I think your attitude to feedback from people who clearly have more experience than you is off putting and it would incline me to believe you lack the responsibility and grit to see a project like this through.