What might be useful could be a modem officially unlocked in order to see & harvest the stats (incredibly useful for trouble-shooting purposes), but disable the ability to change any settings.
Anyone could almost believe that it was fully known that many FTTC connections would be simply incapable of performing at anywhere near 40Mb, never mind 80Mb, due to the sorry state of BT's infrastructure (D-side cabling).
An easy way round that is to to hide the evidence & "blame" any speed issues on contention/cross-talk/noise etc.
Combined with a relatively low FTR, what hope do users really have of resolving connection problems?
I suppose OFCOM fully approves the deceitful decision to hide all connection stats from the people that actually pay to use FTTC connections?