You see, for a while, Konami and Kojima had a falling out. They sort of screwed up Phantom Pain by forcing him to release it early before he was ready. After their disagreement, Kojima decided to go seperate ways from Konami. After Kojima left, Konami retained the rights to the Metal Gear series. They even tried to make a sequel to Phantom Pain, a game they titled "Meal Gear: Survive" which bombed pretty badly as most MGS fans a purists, and those who AREN'T purists pretty much hated the story. As such, it seems unlikly that another metal gear game will happen as Konami would likely lose money on it, and they don't seem like they're willing to let Kojima make anymore. There's a lot of bad blood between them now, and Kojima has already begun a new series it seems called "Death Stranding". Metal Gear Solid sadly seems to have run it's course and come to an end. But I'm grateful that we got a mostly full story that ran it's course. The only thing I can think that they could do is either make a sequel to Raiden's spin off, or make that prequel about the Boss and the Cobra unit that I had heard Kojima referencing around the same time Metal Gear Solid 3D: Snake Eater 3DS came out. But I'm pretty sure it's dead. But rumors are that Nintendo has taken out a new patent on Metal Gear Solid: Twin Snakes (A remake of MGS1 that originally came out for Gamecube) so that they may make a remake to that on Switch sometime, which falls in line with the new Super Mario remakes collection that they recently released.
