Some need a horn but I don’t. The horn on my last car quit working several years before I traded it. I have a motorcycle with a horn that has not worked for at least 4 years.
When riding a bike, your first response when a dangerous situation is encountered should be to get out of harms way, not to reach for the horn button. If you have time to reach for the button to sound the horn, you didn’t need it and just want to blow off steam or get even with an erratic driver. No horn works for me with the car too.
A horn can not educate an erratic driver.