No one's doubting his prerogative to shake things up (not even, by this report, the editors he forced out, who had no problem with the concept of digital initiatives per se). But the main reasons to buy an old magazine, instead of starting a new one, are to gain access to its staff and brand equity, and the results so far are that he flushed those assets down the toilet. It's completely fair to judge him on results.
I don't think that Foer and Wiesetlier "had no problem with the concept of digital initiatives per se". I think TNR had a view of the Internet's effect on culture as something to be defended against. For instance, TNR put out an article in October arguing that readers on the Internet shouldn't post their own book reviews: "I can see the value—maybe—for man-on-the-street reviews of cold cream and pots and pans, but books?!"[1] There are many quotes in the New Yorker article of TNR editors and writers sneering at "new media".
If the goal was to give the magazine some relevancy beyond its shrinking, aging, audience, I don't think that Foer and Wiesetlier were the right people for the job.