She is not designed to be that and isn’t.
She is a very hard boss that you may beat her once per season, yes.
I mean, there are already farmable Ubers, she is just a challenging fight at the very endgame, beating her for most is one of the last things you do in a char, being like a trophy or something. You make her easier and then she becomes pointless.
I haven’t beat her myself this season yet, however I prefer to not do so than making her easier and not an interesting challenge.