What the heck does that mean?
Well, going strictly by the editorial wherein Goldstein lashes out at Netanyahu for being a no-show at Mandela's memorial, "edgier" appears to mean lefty-er. Writes the "edgy" editor:
In his stubbornness, Netanyahu displayed a crucial character flaw: an inability to read the geopolitical winds and act accordingly. The central theme of the memorial in Johannesburg was reconciliation, as it was for the vast majority of Mandela’s political career and all of his post-presidential years. Last Tuesday was a manifestation – a very rare one – of global goodwill, or at least as close as we ever get to it, and Netanyahu failed to take advantage by joining in. That has quite likely cost him points on the world stage.
No one was asking the Israeli prime minister to deliver a eulogy. All he had to do was show up and smile – that would have been appropriate enough. And who knows? Maybe Netanyahu would have learned a thing or two while he was in Johannesburg – such as that great leaders have the power to make us all believe in each other’s inherent goodness, even if the effect only lasts for the briefest of moments.Maybe Bibi stayed home because, whatever else Mandela may have done, he made kissy-face with some of the Jews' biggest enemies. And, really, since the Mandela event, replete at it was with silly selfies, a bogus signer and dictators galore, turned out to be something of a joke, Bibi's decision to stay home is looking rather astute right now (whereas this "edgy" editorial...not so much).