Noise and the NY-accent

I thought that I had ranted about this before but when I was going to link to it I could not find it, so I will now either repeat myself or put forth a stunning theory in written form for the first time:
Observation 1:
Everything in NY is loud, no resources are used to silence anything. The worst places are where the subway goes over ground, sometimes on metal railing over and along street. The noise as the train passes makes conversation pointless. But even inside the subway cars when there are almost no passengers the noise level is deafening. I measured the noise level in a car once when it was almost empty. Result: peak values of 100 decibel and a mean around 90. This is the reality that a New Yorker live in.
Observation 2:
The New York accent is high pitched and nasal, much like a radio newscaster of olden days.
Syntesis:
Just like the old news casters developed their speech to a high pitched forced sound to get through the ether the New York dialect has evolved in an environment with massive noise to the most communicative frequency and sadly towards a Nanny Fine-type of sound.