Is there a list of "hardforks that will never happen in Bitcoin"? The Hardfork Wishlist lists some fork-causing changes that might actually get introduced (e.g. adding more decimal digits to allow units smaller than a satoshi).

Is there a similar list of forks that will definitelylikely never happen? (might happens in alts, but not in Bitcoin)

One such change is obviously changing the target limit of coin creation from 21,000,000 to something else. Another change might be changing the reward splitting to be continous - such a change is probably too complex without much concrete benefit to be ever implemented in core Bitcoin.
Here, I created a page about that: https://en.bitcoin.it/wiki/Prohibited_changes