Before I started playing Sims I played Civilization VI a lot. I had restartitis in that game for sure, because whenever I would sit down and load a game, I would have no idea what the heck I was doing. Also that game starts to feel too much like a management career after a certain point.
In Sims I don't do a lot of restarting exactly, but if I have an idea for a short story or something where there will be a definite endpoint, I keep it in its own save. Also for my games with minisprite, she prefers to have each played family in their own save rather than having a bunch of families together in a rotational game.