Revisiting this after finally getting some progress on a site, albeit non-IPFS and non-crypto integrated as per original vision… there is already a company doing what you described, called Storyful — but in being restricted to that establishment media ecosystem, doesn’t really level the playing field in favor of the many freelancers out there.
That said, I do think there is progress to be made both in the realm of user-friendliness (I share a bit of empathy for this If Users Struggle to Install, IPFS Will Fail ) and in privacy and encryption (protection of identity of people posting sensitive but newsworthy content to be edited into a finished html5 news piece for example).