I'm on a 2012 MBP with similar experiences. Every year I think about finally replacing it, but hold off on it because everything still works fine apart from some increased fan noise and reduced battery capacity (which doesn't concern me too much). If you treat your laptop with care it really does last a long time.
At some point I expect I will stop getting MacOS updates which will force me to upgrade to a newer model.
At some point I expect I will stop getting MacOS updates which will force me to upgrade to a newer model.