No disparagement clauses are a lot like non-compete clauses. I would never sign one, but at the same time, I am reluctant to speak poorly of a former employer or to go into direct competition with former colleagues. I want the right to do those things, but I don't actually want to do them. Now of course, they always say, "Yeah, maybe not you, but somebody." To which I say, "That's why you took so long to check my ref…
You don't have to sign severance agreements that give your rights and employers don't have to pay you severance over what is required by law. If those rights are worth more to you than the severance don't sign.