But publicly traded companies don't dilute their shareholders away. Those shares either have to be sold (meaning the company takes in proportional amounts of cash, driving the value up) or issued as compensation (which you can't just unilaterally in a publicly-traded company).
Your gold example is also very contrived because the futures market doesn't literally dilute away physical gold.
As for Bitcoin: You're missing the fact that while Bitcoin can't be manipulated away from 21 million, the Bitcoin markets can definitely be heavily manipulated by sufficiently large players and insiders. And there does seem to be ample evidence that this is happening.
Your gold example is also very contrived because the futures market doesn't literally dilute away physical gold.
As for Bitcoin: You're missing the fact that while Bitcoin can't be manipulated away from 21 million, the Bitcoin markets can definitely be heavily manipulated by sufficiently large players and insiders. And there does seem to be ample evidence that this is happening.