I'm sure most of your fears could in some form be applied to the horrifying prospect of millions of "thickos" owning and nilly-willy operating ton-sized metal boxes on wheels (concentrated in urban centres, no less!). It would surely be pandemonium, and the end of Human Civilisation if we'd allow that!
I'm pretty sure we had no hope in hell of ever getting cars today with all the professional panic bods weighing in on all the certainly-disastrous consequences (never mind bikes - a fast, heavy lump of metal that can't even stay upright on its own?!? Outrage! Have we all gone MAD?!?)
Sure, people do end up getting killed in car accidents but that doesn't make sane people want to ban them - I'm sure there would be a trade-off with flying stuff too, but you know what let's not go full retard on a "moving at speeds in excess of 50mph is immediately lethal" level...