Well, the Rumanian throne has been vacant ever since King Mihai was deposed in 1947. It was former King Mihai who just took the princely title away from his young grandson. Mihai's successor is his middle-aged daughter Margarita, who has no children. The next in line for the vacant throne is Mihai's second daughter, Elena. Elana is the mother of Nicholas, who until now was next in line for the throne (after his aunt and his mother). Mihai is 94 years old now, and he won't be around forever. In the unlikely event that the Rumanian throne is ever restored, Nicholas's aunt or mother, when their time comes, might very well restore his place in the succession.
Nicholas has only lived in Rumania for 5 years or so. He was born in Switzerland & raised in Britain. His late father was British.
Ultimately it's going to be Rumanian popular opinion that will judge whether they want Nicholas to remain as a royal figure. I'm not sure how the Rumanian people themselves feel about Nicholas, or how they feel about gay people in general. But there's a good likelihood that they may not agree with with old King Mihai's pronouncements.
Incidentally, a few years ago, Mihai also removed his 3rd daughter, Irina, and her children, from the Rumanian royal succession. Irina and her family live in Oregon, and she'd been arrested for participating in an illegal cockfighting and gambling ring.