Oh, heck, I don't know. Maybe because he realizes he's been pissing in the pool, that others are also pissing in the pool, that nobody should be pissing in the

Oh, heck, I don't know. Maybe because he realizes he's been pissing in the pool, that others are also pissing in the pool, that nobody should be pissing in the pool, and the first step to creating a social understanding of "don't piss in the pool" is to put up a sign to that effect. Or maybe it's the evil, mustachio-twirling social justice warriors, somehow hectoring a project worth billions of dollars to its component contributors into listening to little old them. That is equally as plausible.