I wouldn't say they're a thing yet; there are some nice 'luxury' electric scooters, and there are cheap lead-acid scooters, but not too much in between yet.

I'd love an affordable, reasonably well-constructed LiIon scooter, but it's not there. Definitely coming, but not here yet.

Seems to be coming a few now. At least locally there's several li-ion options in the 2k-3k USD range, most with 30-40km range. Quite affordable here for most.