I think I see what you mean, but I'm not sure I agree with all of your estimated outcome. Mostly I think hackers are already doing what you're proposing, and they're usually not getting good publicity for it:
I ran across a device recently that is only supported for Macs. I'm not anti-Mac, I just don't happen to have one right now. But, I think this is one of the things that hackers should spend their time working on. Porting great devices to other OSes when their creator's lacked the foresight to.
There are several examples (I guess the most prominent example being decss) where people have tried to do exactly that. The problem is that when companies often don't release specs because the reason it's only usable on certain platforms is because they wanted to be in control of how and where it's used. I don't agree with this personally.. to me it's like a ladder manufacturer saying you can only use its ladder on a certain type of wall. Companies often see software differently though.
Admittedly, Sony et al have other things they're worried about. They don't care about people reverse engineering their product nearly as much as what people can do with the information on it once they've done so. Even if that wasn't there though, many businesses just feel uneasy about people "understanding their systems". After all, they paid good money for the software side of it to be developed, and they feel as if nobody else should be able to use it. This sort of thing is very precious - particularly to managers I think - and is evidenced by the massive amount of software patents.
So if hackers put effort into porting devices to other OS's to benefit the community, they're essentially doing the same thing they're doing already anyway. ie. Porting devices to other OS's. These are primarily open source OS's, but obviously once there's an open source driver it's relatively easy to get it to any OS anyway.
The benefitting of the community from this is largely disguised by lawsuits and complaints from companies against hackers when they don't like their devices being ported. I think about the only way most people might think otherwise is when devices are ported to Windows. Unfortunately 99.9% of devices are supported by Windows already, and the majority of hackers don't use Windows themselves.
I'm not sure what the answer is to be honest. When a device like the cuecat comes out, it's only a matter of time before someone ports it to their own operating system whether it reflects badly on open source or not. I guess this answer is fairly obvious to a lot of people and I'm not sure if I've added much (I'm interested in clarification or counter arguments). I genuinely think the hacker community is already benefitting the community though - if in no other way, by making it more difficult for commercial to give themselves more control over people than they're legally (and morally?) entitled to.
jesterzog Fight the light