Puccini was the master of opera composition, no doubt about it. This gentleman has some talent, possibly, which could be exploited by proper training and hard work--practice, practice, practice. He was obviously nervous, and except for the high note, he carried it off. Missing that high note might not mean he can't learn to hit it some day, but he needs work, and self-confidence. It didn't hurt that the audience was behind him 100%, and you can't ask for a better back-up band than a recording of a full orchestra playing Puccini's music.
This aria,
nessun dorma, became Luciano Pavarotti's "signature song." So let's listen to Pavarotti sing it, and compare it to Mr. Potts' performance:
Pavarotti sings nessun dorma