It's an interesting question, I think i'd give it less than 10% but above 1%. It's outside their core competency, it involves them negotiating with rightsholders, and there's a bunch of competition coming from existing companies in the space (e.g. Microsoft, NVidia, etc.).
As I can see, their only edge is that they own a global content delivery network which in the best case might be able to give them a few years' head-start in terms of performance vs. other players that don't own IP infrastructure. (It's a recent development that cloud-hosted gaming is even viable from a latency perspective). But that doesn't seem like the core long-term problem; it might give you a first-mover advantage but I don't see that being enough to build a defensible moat in this space.
As I can see, their only edge is that they own a global content delivery network which in the best case might be able to give them a few years' head-start in terms of performance vs. other players that don't own IP infrastructure. (It's a recent development that cloud-hosted gaming is even viable from a latency perspective). But that doesn't seem like the core long-term problem; it might give you a first-mover advantage but I don't see that being enough to build a defensible moat in this space.