The right-wing media at the time latched onto them as the cause of all of society's problems, and Boris Johnson promised to get rid of them if he was elected mayor.

In addition to the other reply's issues, they replaced the dirty and stinking but British-made old Routemaster buses, they were much more accessible to the disabled and babies (pushchairs), they were used successfully elsewhere in Europe, and they use more road space which could otherwise contain an important person's car.

I think they're still used in cities outside London, but that's OK since Daily Telegraph journalists never go there.