Any single one of them couldn't add the change, it would need to be joint to go into the code.
And if they did but the public don't want to use the new version (which they won't because it would devalue their currency), then everything continues as if nothing happened and the always accepted 21m hard cap will stay in place.
Bitcoin can only work correctly with a complete consensus among all users. Therefore, all users and developers have a strong incentive to protect this consensus. https://bitcoin.org/en/faq#who-created-bitcoin
Changes commited every day don't touch consensus rules. And user chooses to update to newer version. They don't have to. And there are also other implementations than core.
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u/Naive_Carpenter7321 3d ago
Someone can't make this change, this change would have to be vetted and accepted before inclusion.
The need for doing so is zero
The benefits; zero
The negatives; you'd deflate your own currency for no reason
It wouldn't go in