Have you ever used a 250w ebike? They are incredibly powerful and they also come with gearing much lower than cars. The power on an ebike does not limit how steep you can go. I took a 250w ebike up a path so steep I had my chin on the handlebars to stop the front wheel lifting off the ground and the motor was powering me up fine.

I did, I had to pedal the exact hill I'm talking about and it definitely wasn't easy; I sweat through my suit because of that. Sold (back to the shop) the bike the next day. Instead of it I got an illegal chinese e-scooter that has 800w and is just perfect in every way. Never had a problem with the police, btw. Sadly I had to give my business to a Chinese supplier instead of local.