Probably my favourite tech talk of all time. I did at least read the actor model paper! (though the 1973 one doesn't say much, you want the one with Baker, "Laws for Communicating Sequential Processes".

I still don't know what he means about not liking APIs though. "Communicating with Aliens", what insight am I missing?

When two humans want to talk but don't speak a shared language, if they spend enough time together, they will figure out how to communicate eventually.

But when two computers want to talk to each other and don't speak a "shared language" (aka, the client specifically must conform to the server's "language"—it's very one-sided in that sense) then no amount of time will allow them to learn one another's rules or settle on a shared communication contact without a human programmer getting involved.