Compiler perspective (fast compiles are a core part of Go, IMO), various tradeoffs(fast compile? fast runtime? binary size? Pick 1 or 2), and seeing code bases that get out of control with generics and such.

Note that, for all of that, I'm still in favor of adding generics in Go, as I do see the value they can add. I'm just pointing out that "bashing" on Go devs on not knowing what generics are or how they can be useful is both non-productive and probably generally wrong. Plenty of us are saying "Man, if I had generics, this would have been less code/cleaner/more reusable!", just the other various tradeoffs outweigh the actual cost of using a different language. Go's ability to drop a very junior dev (or just one that has never use Go) into a codebase and have them be almost immediately productive is incredible.

I think TypeScript is a good example of one extreme. You've got conditional types, literal types, type mapping, and a bunch of other very advanced parameterized types.

(I also think it makes sense for TypeScript given JavaScript idioms; it mainly falls over when the caller has to interpret some very complicated error messages, however)

Try to read code that abuses generics you’ll see what GP means.

"protocol can only be used as a generic constraint because it has Self or associated type requirements"