For me 'win stuff' is almost irrelevant in determining whether I consider a player a club legend. In a team sport, it's hard to judge a player too much on what he's won. We know the level Van Persie has been at. For the last 18 months he has clearly played at the level that can be considered worthy of 'title-winning'.
It's also, annoyingly, silly to expect players to stay at the club for very long periods. By today's standards Van Persie has stayed a very long time indeed. The issue is to do what what he owes the club for his injuries. I'm a little mixed on this. It's not his choice to keep getting injured and the club also don't have any altruistic motive to pay his wages even when he's injured - it's a risk for the club that backfired. At the same time, I do think he owes the club a little more.
But the most disappointing part is the way he has gone about leaving. He was very crafty and he tried to cause the club harm in order to get his way, attacking Arsene in the process. That stinks.