Series producer Noriaki Okamura said in an interview that he is still choosing the next direction.
We gave new players a chance to get acquainted with “Metal Gear”, so I want to continue
He has not decided whether it will be a new remake or a "challenge in the form of a completely new work." According to him, the series has come a long way from pixel graphics to cinematic quality, and each project needs its own approach.
We will not use the same “methodology” as in Delta. Each game needs the optimal path.
The team is discussing further steps, and Okamura hopes for a remake of Metal Gear Solid 4: Guns of the Patriots.
Back then, the "hardware" required special solutions for 3D performance with the technologies available at the time, and the code in Metal Gear Solid 4 turned out to be quite peculiar... Transferring all this now would be a serious challenge.
MGS4 was released in 2008 on PS3 and remains the only part without an HD version.