The primary issue wouldn't be latency. It'd be access to assets (which can easily be tens to hundreds of gigabytes for a modern game) and upstream bandwidth (which is often as little as 5 Mbps for residential users).
These aren't problems that a blockchain can solve. In fact, I'll go a step further and say: distributed graphics rendering, or other computation, isn't a problem which is made any easier at all by the application of a blockchain. It's yet another case of cryptocurrency enthusiasts taking a problem that people seem interested in and claiming, without justification, that The Blockchain Solves This.
These aren't problems that a blockchain can solve. In fact, I'll go a step further and say: distributed graphics rendering, or other computation, isn't a problem which is made any easier at all by the application of a blockchain. It's yet another case of cryptocurrency enthusiasts taking a problem that people seem interested in and claiming, without justification, that The Blockchain Solves This.