I agree that there are plenty of good players in their late 40's early 50's that have very few tournaments in which they can really be competitive. Most of the championship courses that are played in USGA events are set up in such a way, hard and fast, penal around the greens, so that all golfer types can be competitive, and MCC was no different, even after some rain, the course dried out pretty quickly. I have no clue why the USGA hasn't changed the senior am age to 50 to mesh with the senior pro age requirements.
Running into purists and calling the reinstatement practices somewhat controversial in mid-am circles are two very different things. I am a national mid am and we never have had a conversation about it, aside from a jab or two at those who have been reinstated, mid am events much more about camaraderie and fun as opposed to the US Am which is about winning and recognition. I was lucky enough to play in both in 2008 at Pinehurst and MCC so I got to see first hand what the difference was in the two events.
The mid am provides a great opportunity to see friends that you might have made on your college team, or amateur events one might have played in when we were all in college together. It's not until a few rounds of match play go buy that where results are even discussed at dinner, its mostly about catching up and enjoying what is usually a very good golf course and seeing old buddies and telling stories.