I am a tight player, but everything depends on context. I play pretty much exclusively in tournaments, who the strategy is quite different from ring games, because the objective is to win large pots at strategic moments, get the the final table, get into the money, then knock out the remaining opponents, so strategy changes as the game proceeds.
Early in tournaments when the blinds are small, it is best to play very tight, because you need to maintain a stack size such that just one double up and a couple of good pots will put you into a good position at the end of the first hour. By folding as many hands as possible, you allow opponents to make mistakes while you sit back, and they will. Also while folding most hands preflop you can observe opponents, guess their hands, and predict what they should have done, when they are bluffing, and so on.
However, even if you are playing tight, you sometimes need to get into pots with bluffing hands like small suited connectors if a situation with good betting odds presents itself, or if you observe that a player calls everything from the BB with garbage, but always folds to continuation bets.
If you know a certain player will make a pot size bet with any two broadway cards, you may be able to reraise them from the blinds or late position, and then take down a large pot when the flop looks good for you even though you have trash. Also sometimes your trash hits a big hand on the flop, which really disgusts opponents. Just tonight I took down a pair of pocket aces with my 9 6s, so even though I am a very tight player, my opponents might not think so.
If you play loose, you may win many pots, but you will also lose some big pots when you make second best hand, for example you make top pair with Q8, but are beaten by QJ, or you get the bottom end of a straight when opponent has top end, or get a low flush, and are beaten by a higher flush, so this strategy is less effective in tournaments than in ring games, because in tournaments just losing one or two big pots may end your tournament.