I think they make a lot of sense for city commuters who can't claim their train fare. If I commuted on a daily basis the 2.5 mile trip from station to office without tube would save about £1,200 a year. A decent e-scooter is about £500 and would do that journey in about 15 mins.
A lot less hassle than a folding bike.
Even better to have them as hireable Boris bikes.