Benchmarks?

This doesn't strike me as an issue. I can't imagine how you'd draft a statute that would effectively suppress torrent traffic by content. Users just have to encrypt their torrent traffic, which would render ISPs unable to determine the legality of the traffic over their networks. Granted, they could try banning all torrent traffic, but that's a whole different kind of problem..

The "these do not truly constitute creative expression" bit is just a cop-out for them to save face. They just don't want to come out and say "The only reason is that we're afraid of getting sued by the game companies and we're a bunch of poor pussies who can't afford lawyers. So please stop investing in us now that you know we're too poor to withstand even a small lawsuit."

No, "creative expression" is not a cop-out. Whether or not the new work is a form of "creative expression" changes the underlying copyright issues. Machinima is arguably fair use or fair dealing, depending on what country you're in. For example, machinima often amounts to a parody of the underlying copyrighted work, and parodies are fair use/dealing. A simple gameplay video is far more likely to infringe on copyright.

And what does being able to afford lawyers have to do with anything? There's only so much a lawyer can do to help you if you actually break the law. Defending a suit is pretty expensive, but losing a suit (which is what usually happens if you broke the law) can be extravagantly expensive. Complying with copyright law isn't cowardice; it's non-negotiable.