E-bikes can legally travel at 15.5mph. But the fastest the police have seized was capable of 70mph. What will stop the rise of these souped-up and potentially fatal vehicles?

I have 2 e-bikes: a cargo bike, and a folding mountain bike. As per Canadian law they max out at 32km/hr, and can be electric-only or pedal-assist.
Interesting to see differing regulations and enforcement.