That's definitely a part of it - think the Streisand effect, but it's more nuanced than that. Letting certain things just happen and then "fade out" is possible to interpret as complicit support for a concept. If DE wishes to have a stance of welcome and inclusive chat, and they decide that concept is not compatible, they have no choice but to act in that fashion. Likewise, there is a hypocritical tension inherent in stronger enforcement: the community believes DE missed the mark or wasn't paying attention and thus endorsed or at least permitted unacceptable behavior to happen, but the community also simultaneously wants DE to be highly responsive to the rules-lawyering folks who want to debate them about their chat in their game.
Enforcement has almost no upside - practically speaking, the internet gives a megaphone to every single voice. Youtube videos slapping DE in the face, righteous posts on Reddit and these forums, and even Twitter replies to random update posts about unrelated topics actively steal the energy from the DE staff.
"But just fix it by being more transparent and do what we want!"
So they are.
But now people are nitpicking DE's feelings and wording and not validating their point of view, while simultaneously demanding their points of view be validated.
It is a type of hell to be in this adversarial situation. Facebook or Twitter has the same struggles.