Yes, Gleeson could well win an award for his performance. At the very least he should be nominated for an award. Of course competition is fierce and it's hard to say who would win, but one can't win without first being nominated! So yes, for his performance, Gleeson should very likely be nominated for an Academy Award so he has the chance to win.
Jack Gleeson deserves to win an Academy Award for his performance as Joffery in the show Game of Thrones. The portrayal of evil Joffery was not an easy part to play, and Jack Gleeson did it so well that people hated his character. This emotional investment by the audience kept them attached to the show waiting to find out what would happen. This feat was brought by an Academy Award worthy actor.
Yes, Gleeson should win an Academy Award because he has been one of the best actors alive for years now. He has been a profound actor in more than just TV shows and now that he is appearing in movies, he will get a lot of praise from the Academy.
His performance is both difficult and flawless. There is no reason why an actor cannont win an Academy Award for a character that is completely deplorable and unlikable. Unlikeable characters requre a great actor with great skills to pull of as a well, and it is about time an actor won for playing a villain.