Yeah its been known for a while. Its not any more an advantage this gen than it was last gen. You can hook up any external to an X1 or just use the unlimited cloud storage.
I'm sure a few people will utilize it, plus it beats buying a new console just to have more storage on your console. Can buy a 4TB hard drive which will increase your storage 8x and not have to worry about storage for a long time.
Unlimited cloud storage is nice but I personally wont use it, If I upload a movie I have to re-download / stream it from the internet, if my connection isn't so great it means it will pause during buffering or if I'm on a download limit I will be using up my usage to watch a movie I already had.
In Australia the two largest ISPs offer only 500GB max uploads/downloads per month on their broadband plan, with my digital collection it will take 4 Months just to upload the movies to the Xbox cloud storage if I don't use the internet for anything else.
For games also, I can buy digitally and store 8x more games on the console if I upgrade to a 4TB hard drive. It comes down to time also, I dont want to delete games from my hard drive when im running out of space and then when I want to play the game again I have to re-download it which takes some time even with the play-as-you-download feature the PS4 has because it still needs to download core game files and initial game levels.
I'm confident I can fill up the 500GB, but a 4TB harddrive or when the next 6-8-10TB ones start coming out probably not.