Why did Bitcoin’s creator set a hard cap of 21 million coins?
Satoshi Nakamoto let bitcoin has limited supply because he wants bitcoin to have value because limited supply means scarcity.
could anything lead to changing Bitcoin’s 21 million supply limit?
It is possible that the 21 BTC million limit can be changed, but who will wants that? No bitcoin enthusiasts will want that. So we can say that the 21 million BTC limit can not be changed.