That’s a strong assertion. There’s plenty of status codes that indicate something bad happened at the HTTP level but don’t convey information about the RPC.
- 404 might mean the URL was wrong
- 405 might mean swapping POST with PUT
- 404 might mean the URL was wrong
- 405 might mean swapping POST with PUT
Both of these are simple programming errors. You might as well have used the wrong host or protocol for that matter