The influence of his talks show up everywhere and are explicitly called out as inspirations. Elm Lang's time travel debugger, therefore redux, hot reloading work, Observable calls him out as influential, and on and on.
Exactly my point — there's space for those who put together amazing but infeasible-as-product demos to communicate lofty ideas, those who take those and repackage them for "mass consumption", and of course the rare genius who does both, and anything in between.
I feel like putting together a janky tech demo is not especially impressive though. Anybody can think of screens projected onto paper. It's not particularly interesting that the tech demo is possible. Actually making it usable is the really hard part and the reason it remains a tech demo.