I’m making a case for custom codes, not for using a 200 status code with it. My reply said the 200 didn’t make sense.
Of course once you use custom codes, the actual HTTP status codes do become less important, because there’s some redundancy there. That’s not an argument to do it wrong, but it is an argument that accurate HTTP status codes are less of a priority. So understandably some people will take shortcuts.
Apparently you find this very frustrating, but in the end it’s just an implementation detail. But it also sounds like you’re more frustrated with the service API as a whole than the fact it uses custom error codes specifically, so I’m just going to leave it at that.
I think it’s the latter. I once had to take care of a sick friend who was pretty much puking her guts out. Her moans sounded arousing. Of course she wasn’t intentionally doing that, it’s just our own male brains playing tricks on us.