Here’s the thing about this scene.
The war arc is, among other things, the time when the Rookie’s begin to become adults. This is shown most clearly with Chouji, who begins to shed his childish beliefs aside to embrace his inner strength. It’s also the time when Naruto gets his flashback of the first time he fought Sasuke - and the audience was clearly reminded of the person Naruto used to be. A child who had no idea what he truly wanted because no one was around to guide him (it’s a good contrast to Chouji, whose father guided him throughout his life). Naruto has changed. He sees more clearly what he wants. He may not have the answers, but he’s damned going to try to find them. That’s the man he is.
And then we have Sakura.
She’s going to have her own moments later on in the war arc where she starts to truly become an adult. The last big thing we got from her was her denying her own feelings in the misguided belief that it would help Naruto. It didn’t. It never would. Naruto is breaking the cycle of hate and in order to do that he desperately needs Sakura’s (and Sasuke’s) support. However, Sakura’s still got a ways to go before she can play her own part in creating a world of peace.
The first thing she’s got to do is be honest about what she wants. It’s Sasuke. For better or worse, Sakura’s in love with him. She chose him. Love is the key to her strength. Her greatest moments of strength are when she acts out love (in the forest of death, becoming a medic nin, in fighting Sasori). Her weakest moments - in lying to Naruto and trying to kill Sasuke - where the times when she tried to bury her love.
Sakura acknowledging that she’s in love with Sasuke, in spite of everything, is a prologue of her own growth from child to adult. It’s never been about shedding the things she felt as a child. It’s about her being able to understand and act on her feelings with the wisdom as an adult.
The whole of Sakura’s arc is not about Sasuke. But he’s fundamentally part of it. And he’s part of it in a romantic way.
And it’s seriously not one-sided. Sasuke’s growth from child to adult is also linked directly to Sakura. Sasuke needs to come to terms with what was done to him instead of letting it define him completely. Sasuke poking her forehead was the start of him rebuilding his life. He honored his past (replicating gesture of love from his brother) and looked forward to the future (he’ll come back to her). I’ll continue to explain this more in depth as their relationship develops.