Yes, they are handled differently in a legal sense. This comes with some small changes to usability of e.g. bike lanes, but in terms of practicality it's basically still a bike.

Would still be a better comparison, since this is focused on energy consumption. Or just have the car drive slower, as per my other suggestion.

It depends where you live. Here the limit is 400W. Which is probably not quite enough to hit 45km/h in ideal flat conditions.