The support for iterators is relatively new, though being limited to data structures that an iterator makes sense on, they don't exactly get around in the language and pollute everything everywhere.

The support for generics is years old and I don't believe anyone who claims it has ruined the language. I've barely encountered them in the wild and I've never encountered the thing people were really worried about in the wild where something has 4 generic parameters that are themselves complicated generic parameters of other things. If you're encountering that, it is either some one-off library I've never encountered, or it's because you or your team are writing it, to which the solution is, stop that.

I'm not even sure I've yet seen a "generic" in a library in Go that isn't simply straight up a generic data structure, the core use case for generics. I've written a couple of such things but they're all internal code.