Puerto Ricans are US citizens, free to move to the continental US (or Hawaii) any time they like. Once there they no longer have status as Puerto Ricans (except in their minds). In particular they are no longer exempt from paying US federal income tax.
Some Puerto Ricans, but not many, want independence from the US. What most want is a lot of federal money. The island is known in Spanish as "El Estado Asociado Libre de Puerto Rico," (Associated Free State of Puerto Rico). They have a separate Olympic Team and do their best to play the "Wise Latino" card in Latin America. Unfortunately, for them, they are not thought well of in Latin America, being considered a matriarchal society and lacking in machismo.
The woman mayor of San Juan and many other Puerto Ricans have complained bitterly about a lack of sufficient federal response post-hurricane on the island. The electric grid before Hurricane Maria was a ramshackle collection of bits and pieces in which public utility money had been re-purposed to other uses by the management and it took a long time to restore electricity across the island.
IMO the island should be sold to Canada, a country literally lacking a place in the sun. A great many Canadians experience the yearly embarrassment of being guest Snowbirds passing the winter among the Americans in South Florida. Possession of Puerto Rico would eliminate that necessity for sunshine starved people from the far north. San Juan would provide a warm weather port for the Canadian Navy and rum might become a major Canadian export product.
The Commonwealth is not a state and an act of the US Congress is all that would be required to transfer the island to Canada. A "good deal" sale price of around $1oo bucks, US, might be arranged if Canada accepts Puerto Rico's government debt with the island. The debt is substantial as a result of a long term inclination toward artistic improvisation with regard to public money.
Living people of Puerto Rican descent could retain US citizenship if they wish or they could become US/Canada dual nationals like me. Future generations of island residents would be wholly Canadian.
Canada prides itself on its supposed acceptance of one and all. This would be an opportunity to demonstrate that. pl