As noted in the commit message for 8bafe25, which was included in release 9.14.0 via #709:
feat: support React 19
- Drops support for React 15 and 16
BREAKING CHANGE
Dropping support for React 15 & 16 is a breaking change, and according to semver should mean that the subsequent release bumped the major version to 10.0.0. This did not happen.
Technically the right thing to do here would be to deprecate the currently-released versions with a corresponding note, and to re-release all of them (or only 9.16.0) as 10.x versions. Not sure if you'd like to do that, though.