In a startup, the only people who really know the terms of an equity deal would be the two or three co-founders and the funds providing the capital. The precise terms may even be forever buried in non-disclosure agreements.
Naturally, the key tradeoff here is time. With just a few heads making decisions, plans can move quickly.
But if you consider the sheer size of a DAO community, then the process seems to be still pretty fast. Perhaps more importantly, everyone also has an opportunity to participate transparently.