There is a difference between forcing what you believe to be right onto others via legal means, and wanting people to do the right thing because it is moral to do so.
Plenty of companies simply avoid the gpl because it complicates things, and stick to more permissive licenses for their open source efforts.
Plenty more just do what the fuck they want regardless of what the gpl says.
Indeed, and this is why the same thing happens in the BSD world. There are many examples of large and small companies, competitors, working on the same parts of FreeBSD.
Enlightened companies contribute to Free and Open Source software because it's in their best interest, not directly because of the license. Conversely, there are countless examples of companies who don't think it's in their interest, and willfully violate the GPL.
Of course I'm speaking generally, I don't know the backstory here so there might be some other things causing the bad blood. But I would prefer we as a community would not attack people/companies just for not contributing.
I've addressed openbsd elsewhere in this stream.