Hideo Kojima explained during his online radio show (translated by Kotaku), that the bundle is only possible on PS3 because the console uses Blu-ray while the Xbox 360 uses DVD.
"I'm sorry to say an Xbox 360 version isn't being released, because an Xbox 360 version of Metal Gear Solid 4 hasn't gone on sale," Kojima said. "To explain the situation, the amount of data in MGS4 is just too enormous."
If Metal Gear Solid 4 were to release on Xbox 360, it would span up to seven discs, it was suggested. Still, Kojima said he would like to one day see the Collection on an Xbox platform, either this generation or next.
"I want to put it [The Legacy Collection] out [on Xbox 360]," Kojima continued. "But we won't be releasing it. When it's the next [Xbox] console, maybe we can release it [The Legacy Collection or Metal Gear Solid 4]."