One of my favorite video game series was Soul Calibur. A fantasy weapon-based fighting game series where heroes were pulled from all across genres of fantasy. Some of the main characters included:
- A baker girl turned champion of Haephestus.
- A Holy Roman Empire knight.
- A ninja demon hunter
- A samurai
- A shou-lin monk
- A tribesman from the New World
- A Spanish pirate
- A French nobleman swashbuckler
What year was the games set in? 1586. And the pirate has a gun built in the hilt of his sword that was used to wound the priestess of the Greek God.
There is no way that realistically those characters could meet up at that period in history. But SC doesn't care about historical accuracy (if the lizard person is giant golem fighters didn't give that away). Still, I would not really call the game medieval either. To me, it is a fantasy aesthetic that grabs elements from across eras and mixes them with the vaguest veneer of plausibility. D&D does the same.
So if 1586 is "medieval", then we might agree. If it's not, then I don't think we can call D&D or Soul Calibur medieval...