First off, to address the comments about McCartney's voice not being what it once was:
Mick is a singer, whereas Paul tends to be a shouter.
Mick Jagger technically and properly sings, one of only a handful of rock vocalists who ever have, which is why his voice remains ageless. McCartney on the other hand, because he is only sing-talking, and in other cases merely sing-shouting (read
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