Why can't social media companies stop online abuse?

Footballers are being racially abused on social media. Why can't social media companies stop this from happening? An investigation by two New York Times journalists says Facebook's approach to moderation reflects a culture within the company. But social media also gives footballers a platform for campaigning - and even lets them shape their own public image.Guests: Henry Winter, Chief Football Writer at The Times; Joey D'Urso, Investigations Writer at The Athletic; Mayowa Quadri, freelance football writer and broadcaster; Sheera Frenkel and Cecilia Kang, New York Times journalists and authors of The Ugly Truth: Inside Facebook's Battle For Domination.Studio engineer: Giles AspenProducer: Hannah SanderPresenter: Andrea Catherwood