Most services have a lot more systems than OpenAI and thus it is degraded performance when a few of them don’t work. Degraded performance isn’t a good thing, I don’t understand the issue with this verbiage.
When a system is completely broken for most end users, some companies call it "degraded performance" when it should be, in fact, called "major outage".
"Degraded performance" means degraded performance, i.e. the system is not as performant as usual, probably manifesting as high API latencies and/or a significant failure rate in the case of some public-facing "cloud" service.
If certain functions of the service are completely unresponsive, i.e. close to 100% failure rate, that's not "degraded performance"---it's a service outage.
