"As much as"?
Self-voting is a niche weird strat that can pay off if you act really convincing and then turn the wagon. But that's super uncommon. Every time I see it, self-vote is just self-implosion and completely anti-win con (like when you do it). I know communities where it's not even allowed.
Not posting, on the other hand, is sick. It's great as maf when there's other lowposters to blend into. It's great as town PR. It's great when you've been towntelling too hard and you don't want to get NKed. It's almost always a good idea for at least one person every game.