The OP question isn’t really about e-bikes per se, and I’m glad your friend and all other users find them useful, but its really about ever-increasing numbers hogging the existing dedicated cycle paths.
Someone above asked about the situation here in Germany and this may not be replicated everywhere, but I look in dismay at the latest phenomenon of e-bikers forming themselves into clubs *Vereine * and monopolising the sometimes narrow cycle paths.
I’m also a motorist and find cyclists who misuse the rules of the road annoying, just I do as a walker, when in England on a country path, finding it being used by motor-bikes; each to his own.
E-bikes should be licensed as motor bikes and their place is on the public roads. (imo)
It’s OK - depends on your commute and how it feels to accelerate up from there on an ebike (IDK).
Many years commuting on urban / suburban routes tells me that speed = safety. Sitting at 17/18 mph is a nice place to be - you’re part of the traffic rather than separate from it, you can accelerate up when you need to move the bike around the road.
I’ve hired city bikes before that were very under-geared and you feel vulnerable, bimbling along at 10mph, no way to accelerate the bicycle, no respect from cars as you’re not part of the traffic.
If you’re commuting out on the open road it’s a different game as 15, 20, 25 mph on a bike are all substantially below the speed of the traffic so you’d just sit at whatever speed feels comfortable.