Something called Metal Gear Solid 5 Definitive EX was just listed onto Amazon, bringing up the possibility of a new version of the game coming out at some point. The game got acclaim by many but still had criticism for a lack of any really diverse missions, microtransactions, always-online multiplayer, and above all else not being finished.
While the listing for Metal Gear Solid 5 Definitive EX has now been removed, that still lends credence to a number of reasons as to why it might have been removed. Whether it doesn’t exist or it does and just isn’t ready, there has to be some reason as to why it even went up in the first place.
However, this isn’t the “Definitive Edition”, this is just the “Definitive EX”. Considering that the game never got any real story DLC (thanks a lot Konami) before it was released after Kojima was unceremoniously fired, the EX version would likely only include Metal Gear Solid 5: Ground Zeroes, Metal Gear Solid 5: The Phantom Pain, and maybe all of the cosmetic bits of DLC as well, for the price of a single game.
A listing for Metal Gear Solid 5 Definitive EX is likely just a cash grab or a way to get one last bit of money out of Metal Gear Solid fans that they can, especially since it’s likely that no Metal Gear Solid fan will ever touch the series again (both physically and emotionally since Konami has moved out of AAA console games and is instead trying to make licensed pachinko games).
Konami (or at least a representative of Konami’s America division) has expressed a desire to reconnect with fans after 2015 saw the death of essentially all of its fanbase after Kojima was fired and a large amount of information about Konami treating its employees badly also came out, along with the company cancelling Silent Hills.