Ackshually

A retcon has nothing to do with the majority of story points. It means they have changed details in the newer games to contradict what was in the originals. The major plot points and characters stay the same, but small details are either changed or homogenized across the board.

Example 1:
Kyle Schneider survived metal gear 1 and was a Zanzibar mercenary in mg2.

Ex 2:
In mg2 Snake was said to be half British, half Japanese, working for NATO led foxhound. In mgs1, he was American with Japanese ancestry working for the army.

Ex 3:
In mg2 Big Boss tells Snake that he's his father. In mgs1, Snake learns he's actually a clone from Liquid.


Ex 4:

Master Miller went from looking Japanese to a blonde Val Kilmer.

In mgs3 big boss clearly losses his eye in 1964. In mg2, it's mentioned he lost it in the 80s.

In mgs3 it's implied that foxhound was founded in the 70s, where mg1 and mg2 have it being founded in the 90s

In mgs4, they revealed that Big Boss was still alive but in a coma. He was pretty dead in mg2.

In mgs5, Big Boss gets a prosthetic left arm. In mg2, it was said that he lost his left hand battling Snake.

In mg2, Gray Fox says that Big Boss rescued him from a labor camp after the Vietnam war. Big Boss was in a coma for 10 years since before the war ended.

And that's why the games should be remade, to pretty them up and to clear up plot holes