Kojima discussed the subject during a roundtable interview attended by GameSpot, in which he stated that developers have to address sensitive subjects in games if they want the medium to be accepted as culturally significant.
"If we don't cross that line, if we don't make attempts to express what we really want to express, games will only be games," he explained. "If we don't try to go beyond that, we won't be able to achieve what movies or novels have achieved.
"I didn't want to stay away from these things that could be considered sensitive. If we don't go that far, games will never be considered as culture."
Kojima used TV series Breaking Bad as an example of boundaries being pushed in another medium.
"In Breaking Bad, I also see that these guys are trying to go to the limit, trying to take it as far as they can to try to get their message across," he said. "For us as well.
"In games we have to go to the limit, we want to stay within this limit of how far... pushing the boundaries of conveying our message. We look around and we don't see too many games like this. That is unfortunate."
At E3 2013, Kojima said Metal Gear Solid V would be "taking on some very heavy subjects such as race and revenge".
In January 2014, Ground Zeroes was rated Mature by North America's ESRB, which lists blood and gore, intense violence, sexual violence and strong language in the game's content descriptors.