Been riding my 28 mph unlocked e-bike for years. And yet it's still unnerving when I reach that speed, and that's riding alone on an empty greenway. IMO, even 25 mph is too fast for bike paths or shared use paths that aren't basically empty.
The situation has degraded even in the short time I've had my bike. I have to pedal to go fast and it requires sustained exertion to max it out and keep it maxed, so typically I'm not riding at full speed. When I slow down I have to pedal even harder to accelerate up to speed again. So you would think that would encourage dangerous behavior because the cyclist is incentivized not to slow down.
But now I'm seeing scooters and e-bikes where they're not pedaling at all. They're just holding down a throttle and they seem to have no concept of braking.
The throttle jockeys wouldn't have to put any effort in at all when they slow down, yet they never do, while those of us actually pedaling do slow down. They also are rather unfriendly as far as a typical bicyclist will wave at you or nod their head or even say hello sometimes, but not with that crowd. They're typically zoned out with earbuds or whatever.
To me they're a different type of rider and they don't seem to have any desire to adopt bicycle culture or norms. I'd imagine they are responsible for most of the dangerous behavior.