https://www.webmd.com/a-to-z-guides/news/20141121/restroom-h...
Also see this episode of mythbusters, which goes into much more depth than the synopsis on Wikipedia:
https://en.wikipedia.org/wiki/MythBusters_(2013_season)#Epis...
And the high-end ones, which are only marginally better, are very, very loud. Loud enough to trigger tinnitus in myself, for example.
Paper towels don't "waste" paper, they use paper (of which there's no shortage of, in the world) very efficiently. Plus in Germany and Portugal (at least) they have these reusable cloth towels that move between two spools.
If I don't have towels of any kind, I just wipe my hands on my clothes. It's not great but it sure beats the damn useless contraption.