It's a lot more reasonable to use a motorcycle or scooter as your main form of transport when the max speed you are likely to encounter on the roads is 40MPH. In the US you will be sharing freeways with people going 80+MPH in SUVs daily.

As someone who always avoids four-wheeled cages if possible, I can say highways are more or less safe if you have a fast enough motorcycle, compared to slow lane filtering with big vehicles on the road. Tiny spaces, poor visibility, and things that crush you on a slighest mistake is a dangerous combination.

If you look at the "motorcycling countries" (SEA, India/Pakistan, Africa, Latin America, etc.), most terrible accidents happen because trucks share the road with an army of scooters. I've been to a few of them on a motorcycle and it's a nightmare. For the same reason, big cities in China introduced dedicated scooter lanes separated by concrete barriers.