If you are invited for an interview your application is complete. If they invited 172 for interviews out of 569 and accepted 64 that means there was no shortage of people to choose from. To assume that most people decided not to interview is pure speculation. Some people who arent serious about going there still interview as a backup. There is no shortage of people trying to get into optometry school using any channel they can so these newer schools can afford to be selective and still fill up their classes. With all these new schools you do have to ask about the externship sites and residency opportunities. Im sure MCPHS will be lacking in those areas at first. Even at western and rso they had issues with the first few classes as far as curriculum because they kept tweaking things and some faculty came and left as well. Bottom line do your research and know what you're getting into otherwise you're in for an unpleasant surprise.
Except that 569 probably applied to more than one OD school ...probably all of them.