Widespread take up of e-bikes requires broader measures to make cycling accessible. E-bikes are not, by themselves, going to do much to enable most people to cycle.
In the Netherlands, e-bikes help to increase the distances people will cycle and enable people to keep cycling as they get older, but this is dependent on the infrastructure enabling those people to cycle already. In most of the UK, e-bikes will enable people to not cycle 4 mile trips as well as not cycling 3 mile trips, and enable 70 year olds to not cycle at the same rates as 40 year olds don't cycle.
E-bikes are a real boon for some, but they're not going to drive a revolution in utility cycling in the UK. It will take a revolution in cycling, rather, to drive a boom in e-bike use.