I don't think anything is blocking any state from seceding on a legal level if they indeed still had the capability.
We must question then if the United States has any seperation between state and union as we knew it when the union was formed. I would say there is no seperation. Imaginary lines between states are now only a place for 'Welcome to (Insert State)' placeholders.
Rescinding citizenship is a pipedream that only results in the villification of the person or entity seeking sui juris rights. Smoke and and mirrors. Everyone and everything is owned by the U.S.
There were many flaws in the founding documents and leaders. Counting women and persons of a different shade as less than people. This won't stand. And there were other flaws... too many to list here.
The issues of privacy and preambulation have changed. Our rights are not rights but priveleges. Watch as they are so easily explained away and disappear with the twitch of a nose.
And I have said nothing and no one can hear. Unless some miracle of cohesion and unity comes between all people within our U.S. borders there will never be real change. The notion is fantasy.
Thank you for reading between the lines.