I think they are faster on average, although a fit cyclist can go even faster.

I cycle faster than average for Copenhagen, but it takes some effort. I'm not going to bother when I can see the lights ahead are red, or if there are too many people ahead (I may well be unable to overtake safely), or I'm going to turn soon.

Some (only some!) of the e-bikes that pass me don't take this into account. It's very easy to get to 25km/h, and I think it's easy to end up paying less attention to the street as a result. (I have done this myself, when I borrowed one for a couple of weeks.)