I own a £300 Xiaomi M365. I expect it to save me approximately £300 of transport cost before it falls apart.
But I care for it. Rental users won't.
Scooter rental needs to be done using far more sturdy equipment if it's going to truly be profitable (e.g. not a VC pump and dump) in my opinion.
That said, I love scooters - I'll probably buy a better one when mine inevitably breaks. It saves me a bunch of time and is fun to boot. I'm just skeptical of the economics because these aren't like rental cars, they're made of Chinesium, have no suspension, etc. They're built to be disposable at present.
The scooter thing really only targets the college student, and the adult who lives like a college student. Single, spends most of their time on or near a campus be it school or work, etc. It can't really scale past them, because that form of life is extremely limited compared to others and congenial to it.