Or that sound travels across water? I assume it’s because usually there are blockages, tree/buildings horizontally, while in high-rises and boats there are nothing blocking sounds
Edit. The myth here is that sound travels across water and upwards more than any other direction. Apologies if it was not worded well
I’m not sure where you’re running into this myth, I’ve never heard of it before.
That being said, I would hazard that reflection is the idea behind it. Any sound source is going to bounce off of things. Since there’s ground and water pretty much everywhere, or isn’t a stretch to think that someone buying info the idea you’ve presented might think that’s why it’s going up more than any other direction.
Now, the water thing isn’t entirely untrue. There aren’t usually obstacles dampening sound on bodies of water, so it kinda does end up traveling well, despite the water itself not being the reason.
https://www.quora.com/Why-does-sound-seem-to-travel-upward-more-easily-than-it-does-horizontally#:~:text=Sound can seem to travel,upward and travel greater distances.
Here is a question from Quora