Agreed, the virtualisation of the video is what makes storage in...

Agreed, the virtualisation of the video is what makes storage in a blockchain possible. But again, they are not storing the encoded video data in the blockchain so from that perspective what you actually see on the screen is NOT in the blockchain. Instead, they create a small file (a vstub) that has a reference to the encoded video data, that is then wrapped that in a smart contract and that small file is put in the blockchain.