Because Satoshi Nakamoto didn't add that feature and changing the rules of the entire system that existed since the beginning will upset many people who don't want the rules changed.
then you just pointed out the biggest flaw in the bitcoin algorithm.
Even the US constitution has a mechanism to add or remove items from it.. IE: change the rules.
Hi didn't? I disagree. He put the codebase under MIT licensing. Just get a majority of users to switch and you can have anything you like.
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Parenthetically, I see this 'new rules by software upgrade' as one of the enormous advantages if Bitcoin. If the system is abused beyond a certain level, there is a 'nuclear option' available to the community as a democratic institution. This is _not_ an option with gold as a store of value.
Carrying on this thought a bit more, it seems to me that if a large mining pool somehow held together long enough to maliciously destroy the currency, _that_ would be enough to convince a majority of users to 'upgrade' their software to a version which would ignore a malicious block chain fork and 'recover' albeit with some collateral damage.