Cars are loud even if the owner hasn’t made the exhaust louder. Just the sound of tires on pavement, when multiplied across a dozen or more cars, can be quite loud.
This is true, but a motorbike or a chav car is 10 times louder than a Tesla. If it were only the sound of tyres then road noise wouldn't be remotely as bad as it is. I can't wait for the day when petrol motorbikes are banned! (Assuming I am still alive.)
I don’t think it would be fair to ban all motorbikes. It’s only certain types bikes, generally choppers (e.g. Harley Davidsons), crotch rockets and dirt bikes that are loud. Most of the other types are fairly quiet. Although the type of bike probably matters much less than who owns it—-I had a crotch rocket for a while and you couldn’t even hear it a block away.