To those talking about speed governing (not me I love the top speed ! ;-)) that is precisely how the Lectric XP2.0 works and likely all the new Lectric models as well. It is not specifically a governor but it sets the pedal assist top speed in roughly 5mph increments. For example, setting the bike to PAS 1 will only help you up to 5mph. You can go faster but only by peddling just like any other bike or by turning the throttle which again is a choice you are making as the rider. Within smaller campgrounds is pretty much the only time I ever use 1. PAS 2 is 10mph etc up through PAS5. Vast majority of my riding is PAS 3 which is a nice 15mph cruise speed.
I would assume many other electric bikes work the same way but look into it.