Everybody is different. Some folks like high speed on well-maintained roads. Some like high speeds on any kind of terrain--after all, there are folks who do downhill mountain biking! Look at skiiers--there are beautifully skilled skiiers who ski slowly and gracefully--they CAN ski fast, they CAN do bumps, but they like slower speeds.
As for e-cyclists, we have different physical capabilities, different sensory strengths and challenges, different needs, different levels of risk tolerance ....
So, great to have the variety of ebikes. My ebike assist and throttle top out at 24.9mph, from what I can tell. Occasionally I'll notice that on assist I'm going 21 or 22 mph, but quite rarely. I am risk-averse, for sure. If heading to a destination, I like the 15-18 mph range. For recreational riding, I'll put it on PAS 2 and ride in the 12-14 mph range, better to see the flora and fauna, or, if I want a breeze, pedal along in my "destination biking" speed range on "PAS 3". For destination biking, I use higher PAS levels to keep an even speed on hills. For recreational cycling, I tend to keep it on the same PAS. No hurries, no worries!
Happy ebiking!