Sakura wasn't badly written. People just can't let go of their preconceived ideas of who the characters are or how the story is supposed to go. But Sakura's feelings for Sasuke weren't shallow, they weren't based on his popularity or looks, her lesson was not growing past her love because it was holding her back. Her love didn't make her weak or hold her back.... Because it wasn't shallow.
Sasuke was never abusive, used her, or looked down on her. He doesn't have a shred of misogyny in his body. He was always honest and pushed her because Sasuke did care about her safety and he did see her potential. And he did appreciate her kindness. A lot. And Sasuke didn't get a lot of that. Sasuke always supported her growth and was happy for her when he saw it. And he wasn't phased by it because unlike others, Sasuke recognized that potential. The big twist about Sasuke is that he is actually does live up to the hype, but he's not who people assume he'll be. He is a really kind and caring person AND a strong fighter. Or rather, he's a strong fighter because he's a kind and caring person. Naruto teaches us that true strength comes from love and having someone you want to protect.
Lee and Naruto by contrast wanted to treat her like a princess or a prize to be won. And in another story in which Sakura is a victim to an abusive toxic boyfriend that she is infatuated with, Sakura's lesson might have been to end up with one of them. But maybe that's not the message of this story. Maybe in this story, the message all along was meant to be that sometimes women know themselves better than others do and to respect women's choices. And Lee is an awesome guy because even though he didn't get her, he doesn't act she owes him. And Naruto is an awesome guy because he came to realize Sakura wasn't just a prize for him. So the lesson wasn't for Sakura, to realize she liked the wrong guy, the lesson was meant for Naruto, to realize Sakura's feelings and thoughts are valid and to respect her choices. To recognize that Sakura is valid even if she isn't his love interest. And Naruto's maturity in recognizing that and backing off is a lesson a lot of people still need to hear.
