I unlocked the speed limiter on my ebike soon after I bought it. It was easy to find out how by reading the instruction manual - hold down some key combo on the display box and enter secret menu.
Did some testing on my rural road and got up to 45 MPH going downhill in its top gear. It felt very unsafe so I only tried that once.
No, I'm not doing that on sidewalks or around any people. Also I am licensed to drive a motorcycle on public roads.