But...
The last few miles of the approach are still flown at a relatively high power setting with the autothrottles sawing away, flap and gear dangling creating drag etc. That's where the noise is at its worst. Try living in Richmond-on-Thames, Twickenham or Hounslow. You get woken up at 05.17 and that's it, then. We get woken up by the reverse thrust at the aforementioned 05.17 if there's a NW wind component and we're 10 miles from LHR.
I've no doubt CDAs have gone some way to improving the noise environment further out but we've an awful long way to go to making significant improvements in the final approach sector.
Years ago there was a suggestion that the ideal would be the selection of idle power at top of descent with NO additional power applied until shutting down on the gate. Still a dream, I think.
We've a loooooong way to go to making an urban airport neighbour-friendly.
TheOddOne