Racing incident yes, but...
When you come around the outside of someone into a turn you know that is is a risk. Racing is full of risks and you learn to evaluate how big a one you should take in a split second. Lewis Hamilton tried to go around the outside of Webber last year in a similar move and chopped across him. On that occassion it was the man on the outside who came off worse, Hamilton's fault as he knew Webber only had one line to take and Hamilton moved onto it.
Simoncelli had just been repassed by Pedrosa and was probably fuming and frustrated. Pedrosa hadn't got the best line into the corner but was ahead, but also probably struggling to brake enough to make the corner neatly with that line, maybe he wouldn't have made it at all and run on. Simoncelii had a better line into the corner and could afford to brake later but he should also have been aware that Pedrosa could well run wide. He may have thought he could get around him early enough before Pedrosa ran wide. He must have had some small doubt in his mind though that it may not happen that way and that they could touch. That's where the split second decision comes in. Go for it or back off. He went for it, chopped accross Pedrosa who couldn't slow it down enough and they touched, the luck was with Simoncelli that they both didn't go down.
Racing incident yes, error on Simoncelli's part yes, as he had the better view of the situation and could have prevented it. Error on Pedrosa's part, not really as he had the inside, Simoncelli was behind him and he had no idea what he was doing. At worst he would have run on and Simoncelli would have got the place that way, had he backed off. He would no doubt have taken Pedrosa in the next lap or two as Pedrosa was slowing up slightly. He was too impatient but that's racing, he was fired up and the red mist was probably descending.
It doesn't matter what level you race at, racecraft and racing principles remain the same, Simoncelli took a big risk and it resulted in another rider crashing. It wasn't deliberate, but neither was it a fully considered move, more a trust in blind faith which didn't work.
I don't think it warranted a ride through. I'm not sure Simoncelli is the bad boy on track he is made out to be. From what I've seen of him that is.