Personally, the original one makes good sense to me with volume down and up at opposite sides, but this could have come with familiarity. There is some logic to the proposed change, but nothing that I feel strongly about (for or against).
I believe macbooks have the same philosophy, since their order is also [mute/unmute] [volume down] [volume up]. So it must make sense somehow I never really use these buttons, so I have no preference as well.
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