I still don't think that PC gaming would be the strongest platform; even without piracy. Maybe this whole situation it's one of those cyclical things, where the attention shifts from PC to Consoles back and forth. It certainly was the case during the arcade years, then again in the new golden age and now with the current gen of consoles.
yeah, they should be looking for ways to prevent it, Steam is a good example. not only because of digital distribution, but mostly thanks to achievements, friend lists etc.
Building a community it's a good way to ensure a sell, it builds a rapport between developer/publisher and the customer. There is a personal investment on the customer part as they feel part of something and are less likely to take any action that may be detrimental. Then again that it's not a direct mean of fighting piracy.