I ride home in the evenings via Homestead Road, which intersects with Wolfe. Currently, construction on Wolfe causes traffic to back up approaching the intersection, and drivers pull into the bike lane and stop, long before the intersection, even though it gains them nothing. Others pull out from parking lots without looking my way, push their noses into the bike lane, and stop, even though it gains them nothing.
Then of course there are the people who pull into intersections before there’s space for them on the other side, to block both cars and bikes when the light changes. Unfortunately, they do gain from their obnoxious behavior.
If I had a giant, super-loud air horn on my bike, it wouldn’t improve the situation in any way. It might even make things worse. But I’d feel better.