>The original point stands -- the higher resampling rates are increasingly pointless.
If we were talking about sampling rates it would. But we're not, we're talking about bitrates.
Any MP3 of a CD, whether 128kbps, 192kbps, 320kbps or something else, will still have a sample rate of 44.1kHz. Resampling at 128kHz would indeed be stupid and pointless, and would also result in a much larger file than the original CD. That is not what mp3 does; it takes your 16bits@44.1kHz CD bitstream, and gives you a compressed bitstream that will, when decompressed, give you another 16bits@44.1kHz bitstream which sounds similar. The bitrate measures the size of this compressed bitstream, and therefore gives an indication of how much information (in the technical sense) you must have discarded to form it. But it's entirely unrelated to the sampling rate - you can't even say bitrate = sampling rate * bit depth when we're talking about a compressed bitstream.
If we were talking about sampling rates it would. But we're not, we're talking about bitrates.
Any MP3 of a CD, whether 128kbps, 192kbps, 320kbps or something else, will still have a sample rate of 44.1kHz. Resampling at 128kHz would indeed be stupid and pointless, and would also result in a much larger file than the original CD. That is not what mp3 does; it takes your 16bits@44.1kHz CD bitstream, and gives you a compressed bitstream that will, when decompressed, give you another 16bits@44.1kHz bitstream which sounds similar. The bitrate measures the size of this compressed bitstream, and therefore gives an indication of how much information (in the technical sense) you must have discarded to form it. But it's entirely unrelated to the sampling rate - you can't even say bitrate = sampling rate * bit depth when we're talking about a compressed bitstream.