My Ancestor :) - This is canon, BTW

And supposedly Doomguy is Commander Keen's grandson. These two are the great progenitors of the Doom Slayer, the rarely seen overgods that beget the only thing the demons fear.

Respect them.

Revere them.

Wish for the ultimate crossover.

I see your point, but when a creator says something about its work, it de facto BECOMES canon.