I'm not convinced that a triopoly (not sure what it's called) is significantly different from a duopoly.
My own views are that we need a balance of control and chaos. Both extremes have substantual downsides.
My main view is that a centralized system can be built on top of a decentralized one, but not the other way around. And by the way, if crypto and traditional banking co-existed, with broad support for both, that would be a decentralized system, and I'm fine with that. As long as people can easily convert their fiat to crypto and interact with the same sellers in order to bypass censorship.