As long as the State (or government, for those who believe in the possibility of good political government) is "one-size-fits-all", it will be illegitimate. And, if it isn't "one-size-fits-all" it isn't what anyone in current society would consider a government/the State.
"One-size-fits-all" only works when you are dealing with identical, interchangeable pieces. The only thing identical about humans is that they share identical rights with all other humans, and humans are not interchangeable.
With regard to rights and liberty, and only in that case, "one-size-fits-all". In all other cases, "one-size" is more likely to harm almost all.
It doesn't matter how the State is structured, how it is carried out, or what you imagine would happen in its absence.
You can not ethically govern other people without their explicit consent and without allowing them to opt out without giving up things unrelated to the governing.
This is why each human is responsible for governing his or her own life, and no one else's. Yes, some people shirk that responsibility, but your only responsibility in that case is to defend yourself (and possibly others) from being violated.
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Reminder: I could really use some help.