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Except that the boom-and-bust cycle is inherent to markets and there’s an entire cottage industry around encouraging those fluctuations in order to benefit from the arbitrage. It’s a classic pump-and-dump.
Not everyone wants market stability. If you’re in a position to affect the market, or react quickly to it, there is more money to be made in volatility.
By “creating something,” do you mean replacing the work that a human creative would normally do? (That is, replacing an artist/writer/musician who would otherwise have the job?)
That’s where I’d draw the line. I think personal use is fine but if you’re affecting people’s employment by using an AI that’s clearly a no-go for me.