The guy does have a point. What if you prefer B&W over colour?
I don't but it would be nice to show off to friends. And it makes creating faux WWII video's easier, since B&W is already in the game.
Some sort of shader should do the trick.
And I already know it is an April fools joke. I never fell for it, since I was looking for jokes on the internet that day. But I already mentioned somewhere else.
Cheers