I'm arguing that the Moslem military - particularly naval - superiority over Christendom was forever diminished after Lepanto, and it never regained its former capabilities and military supremacy.
According the great historian Hillaire Belloc, "whenever the Turks went on the march, all of Western Europe shuddered". Prior to Lepanto the Turks ruled the seas, and Moslem corsairs terrorized Catholic ships along the Mediterranean. The Turkish fleet had just crushed the Christian fortress in Cypress. They then threatened to enter Western Europe and 'turn the Vatican into a horse stable'. If Lepanto had been lost to the Turks, what would have stopped them from carrying out their threat? Probably nothing!
The Christian fleet at Lepanto sank or damaged nearly the entire Turkish fleet, and the rout came at a relatively small cost to Don Juan's armada. It was, in fact, considered to be a miracle. The Turks never re-established their pre-Lepanto naval supremacy. You're correct in saying the victory at Lepanto didn't end the Ottoman Empire, they remained a power on the land and did eventually rebuild their navy. They also attacked Vienna several more times. But had the Ottomans been victorious at Lepanto, (and they believed it would be easy for them), it would have made them supreme in the Mediterranean and placed them in a great position to attack all of Europe.
There were 80,000 Christian fighters and rowers on the Christian fleet, supposedly the best of the best. Also, when they routed the Turkish fleet they rescued more than 10,000 Christian slaves, (some of them soldiers), who had been forced to row the Turkish fleet. That's a total of 95,000 Christian fighters and rowers who would have been lost had the battle gone the other way, and the Christian fleet would have been lost as well.
I know that there were several more naval battles after Lepanto, and that Viena came under attack several times. It took several more centuries after Lepanto before the final demise of the Ottoman Empire, but from the perspective of the threat they were before Lepanto, the Ottomans were no longer considered invincible, and they no longer had the power or confidence to take Western Europe. Lepanto was the beginning of the end of the Ottoman Empire.