I'm not sure that it's "poison", justifying a recall, without more than anecdotal evidence...at least in the case of Beneful, which seems to be the focus of the article. But, Beneful is an extremely poor quality food and it's not surprising that so many dogs do poorly on it.
A friend has been feeding Beneful to her Lab mix for several years, despite my advice to the contrary..."he likes it". He's doing OK...he's only 5 and a very robust and healthy dog, but I'm sure it won't be of any benefit to him in the long run. I can see dogs with brewing health problems falling ill rather quickly on a useless diet like Beneful.
Best thing people could do is stop buying the food (which is another reason I pester my friend about it!). They won't make it if they can't sell it
It's funny - my recent foster came to me from her owner with a bag of Beneful Healthy Weight formula. When I looked at the bag to see how much to feed, the "weight loss plan" was to just feed your dog less than the maintenance amount! What a novel concept - weight loss by eating less. Why didn't anyone thin of this before?