Adding to MrS's comments. Some of it is down to how the ISPs deal with public demand and givernement drivers. People seem to want "download speed" and targets are always around download.
It is technically possible that the tones used could be reallocated to get greater upload. For example by increasing those used in U0 and U1 however that would take speed away from D1 which could then make VDSL impossible for some users. It is a balancing act and when the various plans were set up a lot of work went into various options to find one which gave the greatest potential satisfaction and usability.
What would you prefer? Say 35 down and 10 up OR 15 down and 30 up?
M H C
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