alt Hacker NewsSomething can be highly succesful in spite of having glaring design flaws. Nobody is claiming go isn't wildly succesful, but it's _in spite_ of these issues. It was clear over a decade ago that iota, gopath, and lack of generics were massive kneecaps to the language; go changing it's mind on those things isn't progress it's just getting the fundamentals wrong.
A good example of where they're kind of stuck is date formatting - it's stupid, unclear, and likely a mistake, but it's not a fundamental flaw; it's just a quirk.
Why is iota a massive kneecap to the language? It is semantically identical to enum in C and Typescript.
The trouble is that Rust is older than Go and it was already confusing people into thinking enums and sum types are the same thing, so by using slightly different syntax, iota, Go avoided the whole confusion of users thinking that enums would behave like sum types instead of actual enums.
Is your attempt at making a point that not having sum types is the massive flaw? Sum types are a useful construct, to be sure, but there are plenty of good languages without them. That's more on the design quirk end, realistically.