(Skip to last paragraph for my thoughts on this article.)
FSF defends the four freedoms of free software, so it's only logical that they wouldn't endorse a distro that encourages people to install software that denies those four freedoms.
On GFDL, I mostly agree with you, but I still use the GFDL. I trust FSF to fix their licence some day (or make GPL4 a real software+docs licence). There's no other body that I'd trust to get it right in the long term.
As for your third paragraph, about FSF's statements not getting enough critical review? You must live on a different internet. :-) People somehow expect all perfection, all the time from FSF. How about commenting constructively instead of complaining about it as if it's set in stone?
...of course, it doesn't help that this article gives no time to FSF's reasoning. (Does FSF have an article that explains it?) I'm not well informed about this issue, but it seems obvious that firmware that's written to be upgradeable will have more extensive functionality. Non-upgradeable firmware would focus on doing the minimal stuff. Put another way, there are three types of software: non-upgradeable blobs, upgradeable blobs, and free software. If we say that we accept the second type, why would device manufacturers ever give us the last type? There's no point in asking for certain freedoms if you permit an infinitely big loophole. More and more stuff would just be migrated into the upgradeable blobs section and we'd just get some UI code.