https://www.tesla.com/ownersmanual/models/en_us/GUID-DEB259C...
For vehicles manufactured as of approximately January 2024: To sound the horn, press the middle of the steering yoke (or steering wheel). For vehicles manufactured prior to approximately January 2024: To sound the horn, press and hold the horn button on the right side of the steering yoke (or steering wheel).
"press and hold" doesn't seem like it'd be easy to do if all you wanted was a quick toot.