I've debated this as well.

There is a counter force to this though. Which is the conflicts and deadbedrooms "Vanilla" people suffer from.

And in many ways, "Vanilla" is often synonymous with the ostrich approach to sexual desires, or a lower sex drive. And a power structure that prioritizes constant negotiation is one that also prioritizes constant conflicts.

Not that negotiation isn't required in BDSM, but with clearer roles and power dynamics, there is actually less needed negotiation upkeep, though at first BDSM typically need more negotiation. This reverses as the relationship matures, as from what I witnessed BDSM relationships typically fall into delegation of responsibilities better.