You are positing that Puerto Rican independence will still carry US Citizenship indefinitely. I am saying the one of the consequences of Puerto Rican independence will be citizenship in the independent country of Puerto Rico. I am proposing that they would have to choose citizenship at that time but at some point they would be an independent country and their status finally determined.
“I am proposing that they would have to choose citizenship at that time but at some point they would be an independent country and their status finally determined.”
Each Puerto Rican would be free to renounce their US citizenship, but they could not be forced to renounce their citizenship.
Renouncing their US citizenship would be foolish as they could be dual US/PR citizens.