It does feel like overreach to me as well. It is a FAANG and they have great lawyers. I hope to never be in a legal kerfuffle with them but regardless I should read more about what they can enforce.

The hilarious thing about their no open source policy is that they sometimes shoot themselves in the foot. Sometimes, they’ll hire someone with a very successful open source project, in the employment contract ask them to stop working on it, then part of the company depends on that software and when it breaks, it causes chaos because the maintainer now works at the company and had to stop working on that open source project that the company relies on.