How about a small list?
I'm challenging your statement because I do not believe there are "Way too many to name", nor were there "Retcons left and right". You're free not to indulge, but if you are going to claim a position, better to make an example.
Kaguya suffered from lack of foreshadowing, yes, though I will disagree that she's the worst, though this is a position we can respectfully have differing views on with no problem.
And no character was "destroyed". No character became OOC at the end, objectively so. They're still the same characters.
I guess a better way to put it would be character regression. Destruction of growth. Sakura was in character for 12 yr old Sakura. Also i said ONE of the worst not the worst, but as you said we can agree to disagree on that. Sasuke's history was retconned. The LAST was a giant retcon and a band-aid on a gaping wound. I'm done with this topic though. I'm not gonna go through every little mistake, like i said i'm done with canon Naruto, it was a great start changed into one heaping pile of ass.