Madden NFL is a counterexample. That game came out in 1988. Not many software companies can say they've been working on the same software series since 1988. Will Dropbox still be relevant in 2035?
Madden NFL is not the only example of a "safe", long-running game series (franchise). Wikipedia has a list:
https://en.wikipedia.org/wiki/List_of_longest-running_video_...