Earlier quoted context omitted.
The areas where these would be used are super crowded, it is likely that the riders are constantly bumping into people.
I see. Why not just limit the speed to that of a fast walking / slow running human and/or fine those who would ride carelessly enough to bump so people would have to remember deciding to ride means taking responsibility? Maybe also ban using smartphone while riding.
And that, dear reader, is where the plan falls apart entirely.
But for real, regulation exists because large groups of people generally can't be expected to act rationally.