Definitely reckless and hopelessly stupid. The kind of thuggery we want to stamp out of the game f'sure.
Two years though? Personally I wouldn't agree with that. That should be reserved for the most extreme circumstances imaginable, like taking illegal drugs, choking somebody at the bottom of the ruck, on field fighting that is totally over blown. Should Williams miss a few games because of that? Absolutely. But I don't think he ever went in thinking "right, I'm going to end your career here and now" .. I think it was just stupidness. It also sticks in my mind how Bismark du Plessis kicked somebody in the head in a Super Rugby game recently. One of the most dangerous things I've seen in the last few years, but I think his four match ban and red card was sufficient. And I don't think this is worse than that. (and I realize du Plessis was being antagonized in a scrappy game so the circumstances were different but still....head is sacred in rugby).
2 years is such a big statement and benchmark to set. You would probably be bound to consider other factors as well, like the player's track record. In Williams case, he probably hasn't had clean hands over the years when it comes to that, lol. I vaguely remember him being in good form for the Blues years and years ago, and then he turned a bit lazy and sloppy. A bit like a Sione Luaki type player.