Are single-brand or single OS sites bad then? I don't understand why having a focus is bad in itself. I'm not sure what you'd expect if you log onto a site with "Apple" in the name. I certainly wouldn't expect to find anything pro-Apple or pro-MS on a site with "Linux" in the name, and similar is true for sites with "Windows" in the name. They all have their own focus and their own audience, and their own preferences biases.
It's fine to have your opinion. You think that Blackberries are better, that's fine. No product is for everyone. RIM has a different focus, and I think that's good. I don't like it when all the major companies try to do the exact same thing, and it's not necessarily in anyone's best interest if they do.
Saying things that aren't true is a different matter. You said Linux is used more than Macs, and it's not been true for a few years, if ever.