>But Alan Kay doesn’t say “use Erlang”, nor does he go into any depths about what the desirable feature set is and what would make it work or would fail to make it work.
Oh yeah? Then how do you explain this lecture where he says explicitly that Erlang should be the modern programmer's assembly?
In my experience, people who criticize Kay for being too vague or kvetching too pointlessly or lacking practical experience in computer science today almost always have not bothered to familiarize themselves with the vast majority of his work before deciding their opinion on it. It's hard to disagree with him that this makes us more like a pop culture than a profession after seeing it.