Wenger has to take the blame, he accepts lack of efforts and genuinely applauds it (he defended our workrate and effort in the cup final and claimed both teams were spotted walking at times and that we put plenty of effort in), unfortunately, with no game plan, favouritism, no repercussions for poor performances and lack of effort and no real tactics or progress it's understandable that players have had enough.
Should have happened a number of years ago tbh, the writing was on the wall even then, with players already questioning our ambition and publicly saying there's no coaching which is shocking to be honest.
Yes some players are plainly not good enough, but then Wenger is the one that brought them in claiming they were super super quality, he could have looked elsewhere.