If they're not going to buy a game because it's not slightly prettier, I'd think that's pretty sad but that's well within their right. I think people need to have their expectations in check though. People need to understand that Pro mode support consists on three things only.
1) The game detects which system it's running on.
2) The game runs at a minimum 1080p
3) The game doesn't run at a worse framerate.
Anything beyond that is not mandatory. Add in taking the Amy Hennig discussion and realize that developers in general are short on time, and short on resources, when something isn't mandatory and caters to a small audience, it's going to be deemed lower priority and when you're short on time to get a game out the door, especially if it means fixing a bug that affects everyone, the non mandatory, low priority feature is going to be one of the first things that gets set aside.
Everyone should keep their expectations in check and realize what Pro support really means combined with over burden developers.