I googled the most trivial of searches and got dozens of responses, here's a few. In any of these cases, is it really fair to say any of these were Uber's fault? Or Lyft's? I do not think so. Do you?
https://nypost.com/2018/03/05/woman-raped-twice-trying-to-ta...
http://www.sun-sentinel.com/local/broward/davie/fl-sb-davie-...
https://www.prnewswire.com/news-releases/rape-victim-suing-l...
https://www.theindychannel.com/news/local-news/boone-county/...
[1] https://www.recode.net/2017/6/7/15754316/uber-executive-indi...
It's carrots and sticks. If a company doesn't do what you want, try sticks (punish them for not doing what you want) and carrots (reward those that do so others see that they should do the same).
Basically, was there something they should have done differently that amounts to negligence.
Incidence rate is similar on both platforms.