The law in my state defines a bicycle as a "device having two or three wheels with fully operable pedals and an electric motor of less than 750 watts (one horsepower), whose maximum speed on a paved level surface, when powered solely by such a motor while ridden, is less than 20 miles per hour". So you are allowed to go faster than 20 if you're pedaling.
Bonus fun fact: in my state, you can't get a DUI on an e-bike because it is not a "motor vehicle".
While true, not many casual cyclists can maintain 250W for more than 10-15 minutes. And 750W is an all-out sprint for many casual cyclists. 1000W-1500W is a sprint for trained cyclists.
So, that 1000W motor is, in theory, as fast as my sprint, but for a much longer time period. And also in excess of the speed limit on a residential street.
Bonus fun fact: in my state, you can't get a DUI on an e-bike because it is not a "motor vehicle".