In November 2021, Lyle Denniston, the namesake of Lyle Denniston Law News, wrote an interesting article about how the hand of congress could be forced to either admit Puerto Rico as State or relinquish Puerto Rico as a territory. Puerto Rico has been a territory for over 123 years.
Basically, there is a legal argument to be made is that the status of "territory" was intended to be temporary. In fact, the Supreme Court has a series of rulings in the 1900's called Insular Cases that essentially stopped the clock on the temporary status of U.S. territories. One might logically think that 123 years is probably outside what would reasonably be considered temporary.
You can read Lyle Denniston's full discussion on another pathway for Puerto Rico statehood here