I'm pretty sure that line of the article didn't mean to imply that we don't know, or aren't sure, only that it goes beyond the scope of the article and isn't directly relevant to the topic at hand.
The promise of privatization of the Telekom was higher speeds and lower prices. The opposite of that happened. This country is now far behind many comparable countries in Internet speed and penetration. And the state, in selling the Telekom, lost the ability to do it themselves when private industry fails. Terrible development.
I've been living in denial about this being a linux specific issue until I saw this post. Eventhough I encounter this problem frequently on linux and it has almost never happened to me on OSX or Windows, I've just been telling myself that it was because of the hardware I was using in each case. If they found a way to fix this, where just the browser froze and not the entire OS, it would be a huge improvement.