fibre not the problem
I don't think fibre to the home is the problem here. I have a FTTC based VDSL product and it's connected at around 80Mbps, however if I'm downloading a file the download speed will only rarely hit 7MB/s usually I see 4-5.
BT have a FTTH product but it connects onto the same backbone as the VDSL so I'd wager a lot of the time the improvement is minimal.
At the same time the amount of data people need to download will plateau the big consumer of bandwidth at the moment is video streaming, but compression techniques are improving all the time. 80Mbps is already enough to stream native bluray content video can be compressed far better than it is on a bluray. Problem is that there are very few services that could cope with a lot of people all wanting to stream video at those kinds of rates.