Whether or not Moyes is cut out for the job has nothing to do with our club captain deciding to get himself needlessly sent off, it has nothing to do Rafael doing his best to join him, or with Smalling doing likewise early tonight... thats nothing to do with coaching, nothing to do with tactics, its down to individual responsibilities. They're some examples, obviously you can go on and on.
First and foremost you pull on a jersey to represent yourself, the club and the supporters. I've never in my life sat in a dressing room and thought, I'm only going to put in 70% tonight because I don't like the manager.
The performance of some of the players tonight wasn't worth the shirt they have on, regardless of anything else. At the most basic levels they weren't good enough. Tonight was an opportunity to get to a final, in terms of getting a team up for it (and I don't think we looked up for it at all until they scored) if professional footballers can't be self motivated at the prospect of a cup final then they're best moved on.