My sense is that popularising electric bikes has a huge impact in cities because it takes away a lot of the physical effort. The first time you ride an electric bike something clicks in your head, and I've seen it in people from all walks of life. It instantly recalibrates your mental radius for cycling, including things like hills etc. The Netherlands is a favourite reference point for cycling advocates, and justifiably so in terms of infrstructure planning, but it's incredibly flat. Electric bikes make that quibble a moot point.
It is very flat, but it's also quite wet and VERY windy. The Netherlands would not be the best place to cycle if it weren't for the infrastructure that they chose to build.
