Disney paid $4B for MARVEL and have gotten a great return.
With paying $54B for FOX, I don't see a MARVEL kind of return for their $$$$.
I don’t see the return being as obvious as the Marvel and LucasFilm purchases.
However, I do think that if this move leads to a successful competitor to Netflix, THAT will be seen as the real return. Time will tell with this for Disney, imo.
Marvel's probably worth somewhere around $15-20 billion on a separate basis, so there's no way the Fox purchase will match a 300-400% return like the Marvel purchase has shown.
But, the real value of Fox's assets will be in the streaming services that are being launched. Here's the basics, an ESPN streaming service can probably get somewhere around 40-50 million US customers based on ESPN's current US properties and theoretical additions (i.e. MNF eventually being available on the service in the 2020s as cord cutting accelerates).
But if you add Fox's RSNs, Sky Sports (after Disney/Fox takes full control), and Star India Sports to that, all of a sudden you create a chance for a far more robust "global ESPN streaming service" with somewhere around 60+ million US customers and another tens of millions outside the US (let's just say 40-50 million non-US customers, mostly European in terms of value).
That's a much more powerful and "future proof" ESPN streaming service. As a sidenote, Facebook placed a $600 million bid recently for one of the major Indian cricket tournaments that was instead taken by Star India (which will go to Disney as a part of this). That just shows what Disney is up against in the future. Creating a much more robust global streaming service would probably be worth twice as much as a basic ESPN streaming service. If I had to project the value added there, it'd probably be somewhere around $30-40 billion.
As for the television/movie side of the business, the gains are less robust there (probably because we will see a reduction in X-Men output and some Fox franchises like Aliens or Apes), but there's still gains.
A Disney-only global streaming service probably gets somewhere like 60-80 million global subscribers after 5-7 years. If you add FX/National Geographic, Fox television studio shows, 20th Century Fox movies/Fox Searchlight, etc., you're probably looking at a service that can more capably aim at all ages and get over 100 million subscribers. If I had to project the value added there, it'd be somewhere around $15-20 billion.
That gets you a total value added of somewhere around $45-60 billion. That's basically a 100% gain over what they're paying for the assets. It's not the 300-400% of Marvel in percentage terms, but it's a much larger gain in dollar value if Disney has 2 robust streaming services with over 100 million subscribers and much broader reach in terms of customers (as well as stronger firepower for buying and keeping sports rights away from Facebook/Amazon/Verizon etc.).