A decade is really tough. Something like WoW has massive resources dedicated to it to continue rolling out content and is probably the best example of longevity in a popular title. It will hit the decade mark in about 2 years time and while they certainly would have had some players who have been with them the whole time the churn over time would be massive.
Wonder what the best example of longevity in a game that doesn't have an element of near constant play required to have the full experience would be?
AFAIK Starcraft and Quake 3 are over decade old and still played. I assume that this days their player base is far smaller than in early days, but they still have tournaments. However they probably did not bring a lot of money for producer in later years because everyone who wanted them already bought them. Quake live if pivot to free to play model but I have no info about its profits.