I keep hearing that when a cryptocurrency is created it goes through an initial setup phase wherein cryptographic parameters are created that are used by the cryptocurrency network throughout its lifetime. I have only a basic and incomplete understanding of this initial setup phase.
What I do know is that if a single person creates the cryptographic parameters for the initial startup of the cryptocurrency they can keep the initial values and cryptographic primitives and can easily subvert the cryptography of the cryptocurrency at any point in its lifetime. Setup can also be done by multiple creators, and so long as just one of them is trustworthy the cryptocurrency network won't be able to be subverted, though there is still trust involved. I also know that RSA UFOs mitigate this effect by making it nearly impossible for the creator(s) to know the initial parameters of the initial cryptographic primitives precluding any sort of subversion; trustless setup of the cryptocurrency. That's about the extent of my knowledge.
I'd just like to know a little bit more about this initial cryptography setup process, why it's necessary for the startup of a cryptocurrency and functioning during its lifetime, why exactly RSA UFOs allow for trustless setup of a cryptocurrency, and why is it that a malicious creator(s) can subvert the cryptography of the network any time after that initial setup phase if they keep the initial cryptographic parameters and primitives.