This just goes to show that you can fold a lot (sitting out folds everything) and still place deep than a lot of players. The early stages is more about the maniacs knocking each other out early in freerolls and micro stakes. This experience you had is evidence that folding isn't so bad. However, as others noted, this is not solely a winning strategy. With less risk comes less reward and you aren't going to get deep runs by never playing a hand. In fact, you want chances to chip up during the game.
It depends on what your goals are. For whatever reason, if you goal is to min cash then folding a ton might be a viable strategy, but the better question would be why you are aiming for a min cash. Sitting out the entire game does not guarantee a min cash at all, but if you are playing nitty, then you need to ask yourself why that is.
Are you playing games outside of your
bankroll you shouldn't even be in? Are you too worried about getting chips in the middle? Are you trying to avoid variance all together (not practical, nor reasonable)? etc.
The better game plan is to be playing for a win, or at least the few top spots. That is where the real money is at in most prize structures and these deep finishes are where most make their real dough. Yes, risking more and playing for a win might mean you cash less often, but it is a valuable trade-off.
Before any event, you need to determine if you are playing for a win or a Final Table, or a min cash or whatever else. Also look into ICM and ICM pressure. If your effective stack is really low, then perhaps folding every hand until you get blinded out might get you to a min cash and maybe that is actually a win for you in this scenario, but in other cases, it would be a crime to not take a chance and aim for the 1st place
