It's possible, but save games constantly modified as player made progress and Blockchain isn't suitable to keep file changes (especially non-text file). If the blockchain only needed to keep purchase verification keys, then there shouldn't any problem.
But if you don't need database which is distributed, immutable and have no central authority, you should use Distributed Database instead.
And didn't Freenet already invent uploading content in a decentralized way? It's some ancient software, I never tried it but I think you basically uploaded stuff into a network of computers and everyone stores everyone's else files and it's everything encrypted. Im not sure what the difference of this and a blockchain that stores files would be.
IPFS and Filecoin also attempt same goal, but the reliability/up-time of those (including Freenet) isn't very good as not everyone forced to store same file.
I see, so the main point would be the blockchain which is immutable, but as I said before, you are going to need massive amounts of PoW for that to work, and thus far, I don't see how it's viable to store big files in a blockchain an decentralized therefore immutable way, that is why only Bitcoin makes sense.
I remember reading about Factom I think it was, some altcoin that attempted decentralized data storage, I haven't heard from that in ages tho.