"Did Dennis Ritchie have a hand in creating Go? I must have missed that."
Oops. You got me on my bad memory there. I misremembered Griesemer. The C language was originally just B modified with structs to try to port UNIX from assembly. Also, the limited keywords & "programmer is in control" philosophy came straight out of B. The details are in this nice Vimeo that traces its development going through papers they presented:
https://vimeo.com/132192250
"An expert in windowing systems and concurrency"
Even if we drop "language" expert, my comment had him bringing in concurrency mainly. I didn't know Cardelli started with Newsqueak, though. Makes sense given stuff as good as Modula-3 rarely comes from a vacuum.
"Articles like this one[1] by Pike only serve to reinforce my thoughts that he, though a rather smart guy otherwise, is really rather ignorant about language design and about the role of types in programming in general."
Well, see, it's been given a test. The Concurrent Pascal, Ravenscar, and Eiffel SCOOP approaches to concurrency were all very effective for what they're designed for. I've been sitting on the bench on Go watching it from afar to see what Pike's method does. So far, I see a lot of people griping about concurrency errors that didn't happen in SCOOP. Meanwhile, Rust has improved on things in a new way. Your characterization of him as an experimenter more than an expert may be right.
"None of Wirth's languages had GC until Oberon, as far as I'm aware. "
All of his languages except the first two that he started with. They made a lot of languages. It's kind of a strength and weakness of theirs as doubling down on a great one might have accomplished more. Might given Cardelli did without much direct impact.
"Oberon, on the other hand, was a very spartan language that offered little in terms of features"
So was early C. It's why I bring up Modula-2 or Oberon in comparisons as nobody is writing or deploying Modula-3 or Ada on a PDP-11. I'm not a fan of Oberon except for bootstrapping better languages or for minimalist hardware. Even then I'm more PreScheme.
"Later versions of Delphi grew to C++ levels of size, complexity, and hairiness"
Snowballs rolling into avalanches. Common ill in tech although I think it's human nature or economics more than anything. It takes a cathedral model that prioritizes just right amount of complexity to avoid. I just subseted languages like embedded people do to avoid the shit. Until I had to debug a 3rd party library. (shakes head)