Inevitably in all cases language-specific problems exactly like this happened, but also just some frustrating drift. One of those heroic workhorses would go out on parental leave and maybe a backup would go on vacation or out for extended sick time and the SDKs would start drifting away from the API. Someone would be stuck maintaining code in their absence. At one point, I (a product manager at the time) got tasked with maintaining a Perl SDK while a developer was out on leave for several months because my background is in software development and I was the only person that could really maintain it in the company.
I'm happy to see tools like this come about because it seems everyone underestimates how much work SDKs take to really build functional SDKs. You can get bad ones cheaply by just putting a few people on and accepting bugs and drift. The counter-argument against these tools that I've generally heard is that they'll also produce worse ones cheaply or require effectively the same maintenance to figure out a machine-generated problem as a human-generated problem.