Series creator Hideo Kojima did not contribute any to the creation of Snake’s Revenge. He did call it a decent game and thought it was true enough to the Metal Gear series.
When Hideo Kojima made Metal Gear for the MSX, it had disappointing sales in Japan. But the inferior NES version was a surprise hit in America. Konami made a NES sequel called Snake’s Revenge and one of the programmers on there talked to him and inspired him to make his own sequel.
Hideo Kojima was partly inspired by the 1963 war film The Great Escape when making Metal Gear on MSX.
Solid Snake on the original boxart of Metal Gear was literally drawn from Michael Biehn portraying Kyle Reese in the original Terminator movie.
Many found it odd that Solid Snake fights a super computer instead of a Metal Gear in the NES version of the original game. The reason was mainly technical, as programmers couldn’t fit the nuclear tank properly with the limitations of the hardware.