Do we want to change how this is handled at https://github.com/dart-lang/watcher/blob/562b9e588eb7abf5e734be04b4b710ca013764a1/lib/src/file_watcher/polling.dart#L65

I don't think we want to change the logic in the file_watcher. A user is explicitly providing a path to watch and therefore would like want to be notified of watch errors. The directory watcher is using implicit file paths due to the polling logic.

A user is explicitly providing a path to watch and therefore would like want to be notified of watch errors

I don't think it would be considered an error. We handle the removed case at https://github.com/dart-lang/watcher/blob/562b9e588eb7abf5e734be04b4b710ca013764a1/lib/src/file_watcher/polling.dart#L57-L61 - we just have a potential race condition for if the file is removed in between our check for exists and our file stat.