It happened to me last week when I tossed my coat forgetting the phone was in the pocket. I was very confused when I came back 30s later and dispatch was on the speakerphone asking what the emergency was
Since a false positive generally causes much less harm than missing a true positive making no false positives a requirement is generally a terrible idea.
As I mentioned in another post, Apple shouldn’t be farming out the determination to emergency services. They can provide an intermediary to determine the severity. The situation is such that a phone or watch does not have enough information to properly evaluate a situation as an emergency or not.