Yes, other companies are doing it but it's not the point of the article.
What I think me and many others are starting to wonder is why is it almost always Apple that's singled out? I could probably find 20 items in this room that were made by Foxconn et al and don't have an Apple logo on them. But there seem to be constant articles, radio news segments, one-man plays, etc criticizing Apple's labor practices specifically and nearly none about any other company's products — when there are non-Apple-specific discussions of unfair labor practices, they tend to refer to broad generic terms like "the electronics industry".
My guess is that at least a part of it is because many of Apple's users have such an emotional connection with their Apple devices that go everywhere with them — it "hurts" in a way to hear about one's iPhone being morally questionable in a way that it doesn't to hear the same about your Xbox.
Edit: I am not making any judgements or criticisms, this is just an observation on why people feel the need to criticize.