Because it isn't solved yet.
You are a gold member...go to the opening explorer play some opening like the sodium attack.
(1.Na3 named because Na is sodium probably)
It is a dumb opening but just look at the number of games played.
exactly 5.
This isn't an optimal oppening of course but there are a lot more openings.
Many good opening aren't popular just because some are better.
Chess is fun because it hasn't been solved yet.
It is immpossible to play perfect chess.
Sometimes even decent chess is not enough.You don't need to try something different to be put on the backfoot.
There are machines that can lift much heavier weights than humans. Even the best human won't lift as much as a forklift truck. So why do humans still train weightlifting ?