This is about how much noise your aircraft are allowed to create. What you should be able to hear in the street are "the tweeting of birds in the camellias, the tinkle of coffee spoons and the sound of human voices".
I'm with you regarding motor bikes and public transport but the same rules should not apply to the others. They can have their own rules.
http://files.meetup.com/4709972/Leaf%20Blower%20bans,%20etc....
To suggest this new vehicle has to operate at a level to not drown out birds before it can fit into society is silly. It's reasonable to place restictions on their use, e.g. you shouldn't be able to takeoff and land in quiet residential neighborhoods, instead limit them to landing on the tops of very tall buildings or transport hubs.
Also, if people are allowed to use lawnmowers and loud exhausts on motorbikes, and have been doing so for years, suggesting a new technology has to be subject to more stringent restrictions is a little unfair.
To be clear, I really dislike noise pollution, and welcome the day when noisy lawnmowers, leaf blowers, jetskis and motercycles are banned from where people live, relax, most places really. I think it is really selfish for others to produce such noise around others.
What is silly is to say this noisy thing can't possibly fit into the world without hitting an extreme benchmark, when society has already accepted much worse offenders (whether you and I like it).