Users of Vespas and Lambrettas are largely not a nuisance: they don't ride on sidewalks, utterly disrespect traffic rules while endangering themselves and others, and are generally properly parked (at least well enough to not be a noticeable nuisance).

There is probably a link with them being more expensive, requiring a licence, being registered and the fact that they are not perceived as a nuisance.

I really doubt e-scooters users are going to jump on those in numbers large enough to make a difference.