I would think people would get used to the noise though if they have lived there a long time. I've always lived by a highway with noisy trucks going by often, and it doesn't usually bother me. If traffic noise is such a problem, I wouldn't think they wouldn't even move to a location that needed that much work to help muffle the noise.
Though I do like the aspect of creating visual barrier from the road. but I'm thinking that alot of places, a berm couldn't even be contructed. Alot of limitations with that. Maybe a wall that takes less space could be contructed, but would cost alot more I would imagine. I'm using plants such as fast growing hybrid willows as my visual barrier in the warm months when outside more.