Agreed, this is his last shot at it. If he's ever gonna get another title shot, he needs a big W over Thiago on Saturday.
I disagree that this is the best he's ever looked in his UFC career though. When he first came into the UFC, he was an absolute killer. He entered the UFC on a 15 fight winning streak, and won his first 5 UFC fights with some impressive finishes over decent competition. A lot of people actually thought he had a shot vs Jon. His recent 4 fight win streak is nice but the competition hasn't been that great and he looks noticeably slower to me. He is the underdog vs Thiago and rightfully so, but I'm definitely not counting him out.