IME off-the-shelf e-bike riders are some of the best-lit cyclists, as nearly all of them (apart from the more serious mountain bikes) have StVZO-style lighting. I see very few conversions in the wild these days (those little petrol engine kits are almost as common), but I expect they're more prolific in That London: Birmingham seems to be going through an e-bike revolution over the last couple of years, much like when Bromptons started appearing in the mid 2010s. Tern GSDs feature strongly, as do minimum-viable-folding-EBSOs.
Scooters and related exotica (skateboards, unicycles, etc) are ridden with whatever stock lighting they come with, which is frequently none and sometimes purely for aesthetic reasons[1] (blue downlighting and similar). The Voi hire scooters and Beryl Bikes are pretty well lit.
[1] I got overtaken by a strangely lit electric scooterboy on a dark lane last summer, and briefly thought I was about to be abducted by aliens.