The problem is that Maleficent even feeling regret for what she did, much less trying to redeem herself for it, goes against the entire nature of her character, basically Disney’s devil figure. It would be like, to use an example, Frieza from Dragon Ball all of a sudden regretting his misdeeds. Heck, in the original movie, she wasn’t even motivated by revenge, that was just an excuse, she just loved being a heinous villain.
Not directed at you personally, FRiend, but we what the heck is everybody talking about?! Really? An entire intellectual discussion thread about a Disney character??!! Sorry. ‘tis to laugh.