To be fair, it's exceptionally difficult to judge a writer based on their past work. All of those films had other hands shaping the project - so it's hard to distill what he's contributing (and if he's a positive/negative element).
But I don't think this is a good sign. They approached him, rather than take an existing pitch. Meaning he didn't come in with some idea for MGS that was so phenomenal that they hired him on the spot - instead, they tossed a talented guy their hot property, and said "adapt this, we'll give you a fat check."
I think you could make a great MGS movie. The structure is already based on action movie tropes, so it's just natural to turn the switch back & make an action film out of it. But it also needs to be something more. It has to be clever and subversive to the expectations of film, the way the original subverts that of games.
Expect Bradley Cooper as Snake, Emily Blunt as Meryl, and an inexplicably buff Ralph Fiennes as Liquid.