TfL mandated black cabs must - as a condition of license - take card payments, almost certainly in reaction to Uber's claim that they were serving a cashless society that other options weren't.
Black cab drivers also got into Halo and other apps for ride hailing, and there are now a few other third party private hire apps for non-Uber drivers. I also think it made Addison Lee - the largest private hire company in London pre-Uber - shake their game up a little.
A few people will complain, but genuinely, London will be a better place without the fleet of thousands of Toyota Priuses circling all day, every day being driven by people who TfL suspect are not fit to hold a private hire vehicle license.