It looks like the study is linked? https://iopscience.iop.org/article/10.1088/1748-9326/ab2da8

Also, it includes the scooter company driving around at the end of the day to pick up all the scooters. Obviously not applicable if you are using your own personal scooter.

And using a scooter instead of a car means traveling far fewer miles and covering far fewer square miles of your land in car parks, so other people don't have to travel as far either.

There are situations where I've considered using an e-scooter because existing infrastructure is insufficient or just plain unreliable. If a bus or two or three are cancelled and I'm really frustrated, even a car seems like a great solution, regardless of environmental cost. E-scooters seem like a decent alternative (depending on how reliable and environmentally friendly they actually are). I'd even consider buying my own, but it seems Germany is lagging behind in allowing e-scooters in public (the only two models that are purchasable that are also street legal cost 2000+ Euros).