Better late than never I guess.
There's also the difference between being familiar and knowing things in-depth; I was previously aware of the broad strokes of Ada and many of its features, but only at a high level. The point is to deepen this understanding.
(Also, I'm not on the language design team.)
I don't know why but after that talk I always assumed you played a role in some of the language design.
I mean, I think that's fair: usually, people who can speak deeply about the tradeoffs made for particular syntax or features are the people who were directly involved in making the decisions. I just read the discussions between all of those people. If we didn't have the RFC process, I wouldn't have so much context.
But yes, it's weird. First, he's not a designer of the language. Second, there are too many languages for anyone to be intimately familiar with all of them.
And third, there's just this weird bunch of very negative comments. What's up with that? You don't like Rust? (Not you, lukebitts, but the original commenter.) Fine. Don't use it. You don't like the publicity it's getting? You think your language is better? Languages are tools; they're not rock bands. Feel free to like and use yours. Rust doesn't take anything away from that. You don't like Steve? You think he's getting too much attention? He's getting it for useful, informative contributions. You want that kind of attention? Go and do likewise, rather than whining and sniping because someone else is getting attention.