The 38-year-old came into the Champions League contest at Parc OL under pressure having committed costly errors in his previous two outings for club and country.
But he was at his absolute best on Wednesday (AEDT), saving an Alexandre Lacazette penalty before pulling off a stunning reflex stop to deny Nabil Fekir.
Juventus went down to 10 men soon after that save as Mario Lemina picked up a second booking, but Buffon remained inspired and Juan Cuadrado's rasping shot snatched a victory that puts Juve on the cusp of the last 16.
"People can organise my funeral, but there's nobody there," Buffon told Mediaset Premium.
"I have said many times, without arrogance, that I am very self-critical and don't need to listen to others who try to use situations to disrespect and show a lack of fairness to people.
"I've heard many stupid things in recent weeks, but just one true comment: 'I expect more from Buffon.' That is true and I agreed with that wholeheartedly."
He said of a scrappy overall performance from the Bianconeri: "Juve must improve, because this is not enough in my view to go all the way.
"We seemed more compact and more like a team once we went down to 10 men. We managed to suffer under pressure, but also weren't just happy with a point, and that shows our spirit.
"We have the opportunity to do a lot better and it would be a real shame if we didn't use the time leading up to the next round in March to step up a few levels."
Cuadrado was also delighted with his impact on the match, describing the slightly hit-and-hope nature of his stunning winner.
"I am happy and thank God. I tried to make the play, looked up and couldn't see anyone in the middle, so I tried to hit a missile and it worked!" Cuadrado said.
"It was a very difficult match against a great side like Lyon, but I think we put in a strong performance, a real Juve game with a man down and showed our character.
"The objective is to top the group. Now we must turn the page, as we have a very important head-to-head at the top with Milan in Serie A this weekend."