Here is a new , old school , bobber, and the Harley is more on the lines of a bobber.Bobbers were what led to choppers one hundred plus years ago.
Here is a genuine Excelsior hill-climb bike, bobbers came about as riders removed anything not needed for competition, and then the bike often was there reg. transportation.
Right now bobbers are the in thing for riders who are not cruisers, and even the crotch-rockets, for them running without the fairing is in, they call them "naked bikes" which to me is silly as I rode both with and without and would never ride without if I did not have to.