I can only go by what I've seen on YouTube but I've got a couple of pilots in my subscriptions and they have a ton of information about the airports and fields they are flying into including approaches for noise considerations, etc. and would not be significantly deviating from instructions, especially not a commercial pilot whose livelihood depends on it. Any significant deviations without authorisation they get quickly pulled up on and having to justify with a very real chance of getting their license suspended. So I highly doubt they are flying far enough out of restrictions it makes a material difference to noise.
Here is a how it tends to play out heh https://www.youtube.com/watch?v=tzy9jCFk0Iw
Here is a how it tends to play out heh https://www.youtube.com/watch?v=tzy9jCFk0Iw