Tight play will absolutely win in soft, low-stakes games where most of your opponents are playing loose.
In tougher games, it helps to be loose (at least in certain spots) to remain unpredictable. If you're very tight, you'll also need to modify this for short-handed play. By the time you get to 3-handed and heads-up in particular, loose-aggressive play is definitely the way to go.
If you're in soft full ring games, continue playing tight, but you may want to look at a few ways to open up your game such as raising wider in late position.