I appreciate that people are including Click in here. As noted already, we don’t want to continue to vendor optparse, as it doesn’t match how we actually process args, and I’m working on removing it. That said, Click is not “better” or “more correct” than any of the other CLI processing libraries, it just picked different features/patterns to support. The fact that we don’t want to depend on optparse doesn’t mean optparse is not useful. I doubt one library is going to be perceived as correct by all users. That’s sort of the problem with maintaining a CLI library, different users have different expectations, and so they make requests and you have to figure out if each fits or not. The more configurable and dynamic the library becomes, the more potential there is for unexpected combinations.
All that said, I think the current policy of “getopt and optparse are complete, they’re not being removed but they’re not being changed either” is fine; perhaps change the wording to that rather than “deprecated”. Especially as otherwise the policy is “we’re maintaining three different CLI libraries at once”, which I don’t wish on anyone. 