That's my point about regulating the noise, not the tech. But objectively, I the electric ones I have heard are way more quiet (though still obnoxious). The gas ones basically sound like a chainsaw, and are louder and have more jarring harmonics.
I think you're right. Googling around most of the sound is generated by the air movement, but ICE blowers seem to be ~1-3 decibels louder, but may be a bit more powerful.
Personally, I'd advocate a rake.