Lucky Star and K-on for CGDCT
Evangelion for meta-commentary and deconstruction, to the point that future works that qualify often get called the “Evangelion of <genre>”
Fullmetal Alchemist Brotherhood and Attack on Titan for battle shounen
Bocchi the Rock for girls band anime, specifically
Lupin III: The Castle of Cagliostro for pretty much all of Ghibli
Akira for 90s anime
I’ve been waiting for people to mention the first few magical girls. Basically all my knowledge on the subject comes from Kenny Lauderdale videos, I would have suggested Minky Momo or maybe Creamy Mami. I’m not actually sure how wide-reaching their influence is.