I don't think it's making fun of Mortal Kombat. Moreso, I think it's mocking the AAA games industry as a whole.
And it wouldn't surprise me in the slightest if this becomes a real game some time soon. Amazon's partnership with Netherrealm may go beyond just Homelander as a playable character in MK. A small $30 game with reduced graphics and a smaller roster would probably do pretty well, and I have a sneaking suspicion that one of the reasons MK1 feels so barren is because they had a small skeleton crew working on a The Boys game. Idk. Just a theory.