This single part of that collection is an HD port of a PSP game. It's not a remake and can't be compared to MGS:3D. which is, you know, a remake. They just said Peace Walker would be in the collection. They didn't say they were rebuilding it from the ground up to be optimized for your $1500 TV. I'm sure the rest of the collection will look fine with some hi res texture touch ups, but it's difficult to just touch it up with a PSP game.
In the long run, you get what you get, and other people will be more than happy to buy this. It's the accessibility of Peace Walker and the online that are going to get people playing this now more than anything.