Okay, enough with the downvotes. What's wrong with my question? I didn't mean to bash a field about which I know next to nothing. My question is genuine.
Now I do have an idea where trading could be useful. For instance, a good old merchant doing arbitrage and making a profit is pretty useful: that's how different regions can specialize, do better than they otherwise would, and ultimately lift us from hunter-gatherer tribes where 60% males die a violent death, to our civilization now. And money, as evil as it may be perceived, is to date the best organizing medium humanity ever had.
Investors also have their use: by better allocating money among companies, we could hope to give more money to those who are better at converting it to actual wealth.
But.
The OP didn't make a ton of money because his model of the the companies had an edge, but because his model of the behaviour of other traders had an edge. So I fail to see what useful information his trading put into the system. How his actions resulted in better (or worse) allocation of money between companies. How the (very serious) game he was playing was anything but zero sum.
Maybe there's an error in my reasoning. In this case, I'd happily accept downvotes, but please tell me where I have gone wrong. Not understanding why one's post is being scolded is just frustrating. Like failing an exam and being told to have a hard look at oneself. "Yeah, I get that, but what should I look for?"