The first few responses are clearly canned (the text equivalent of an IVR, but better implemented), but then I get to a human within just a few seconds of prompts and maybe a minute or so of waiting.

The humans I've gotten have unfailingly been helpful and effective at solving my issue. Every time. I don't care where in the world they're located; I care that my problem gets solved and they've been 100% track record on that (or as close as possible to that; if I needed something today and the package is late, they can't magic one up onto my doorstep tonight, but anything short of that, they've solved).

It's also maybe 1 in 100 orders that give me any cause to contact them in the first place.

The obvious question is what type of issues are you having? Typical shit like returning an item you ordered would have a set process. Returning items you didn't order is probably a lot more confusing.

As a typical online customer, I have typical online customer problems (late delivery, more rarely wrong item). I agree that Amazon has rightly optimized to handle the problems that their customers typically have. I'm not sure how that relates to this thread on local humans vs overseas humans vs text automation of responses though.