It actually depends 100% on the trail or road you’re riding on and how it’s licensed.
You can have a pure electric motorcycle with throttle licenses for street use. No power or speed limits (obviously).
But most bike paths have been designated “No motorized vehicles” from the time before e-bikes. There have been exceptions carved out in some places for pedal-assist bikes, but having a pure throttle would not comply with the pedal-assist requirement.
The problem is that e-bike companies know that a lot of people really don’t want to pedal or be limited to 20mph or 750W, so a lot of the e-bikes you can buy today are easily hackable by design. It’s common for people to buy an e-bike compliant with these regulations and then immediately modify it to remove the limits and add a throttle. Now they have an electric motorcycle that looks like a compliant e-bike from the outside.
And to be honest, they’re ruining e-biking for everyone. My local trails are filled with people flying around at motorcycle speeds while the rest of us are moving at pedal speeds. They’re tearing up the trails because they can put 1500W or more into spinning the rear wheel without feedback while the trails were designed for us manual bikers putting a few hundred watts at most into the rear wheel with direct feedback to feel any spin.
Locally, there’s a backlash of denying any e-bike from common trails because they’ve morphed into a loophole to motorcycle around. It’s unfortunate because I really wanted pedal assist e-bikes to open the sport to older and less physically fit riders, but instead it’s closing the sport to anyone who doesn’t feel like dodging kids zooming around at twice the speed anyone expects.