I was always in the minority that said either 1. Sasuke had to die. Or 2. Sasuke had to lose something very important for him to stay alive.
I still feel like the best outcome for this story would have been Sasuke in the end giving up his life after realizing how much he had ruined the people who actually cared about him, and how selfish he was being. If I had my way Sasuke would have died sacrificing himself to beat the Rabbit Goddess.
The other possibility, if he was to live, was that he'd have to lose something that connected him to his sins. Many people back in the day used to theorize that Sasuke would end up losing his eyes, and his power, and therefor go from being one of the strongest (if evil) people alive to relatively weak and harmless. Some predicted that he would end up becoming an advisor to Naruto when he took over the village, as a guide and constant remind about what is lost when someone becomes obsessed with revenge.
What does that have to do with what you were saying?
The confession and attempt to kill Sasuke in the first place, was for many of us a step along the way to his end.
1. Sakura ultimately rejecting her shallow girlhood fantasies about getting with the "hot guy" after it is shown that said hot guy was killing the people she cared about.
2. Sakura coming to terms emotionally with her actual feelings and what matter to her. This brought her to her act with Naruto.
3. Her attempt to kill Sasuke was genuine, not out of hatred completely but also because she needed to protect what she really loved. Not just Naruto but her village and friend as well. A rejection of childish ways.
4. After failing (as the story would have dictated), Naruto and Sakura would have to address each other's feelings more, and develop their relationship further. Even if it's now Naruto who refuses to see what Sasuke is doing and instead it is Sakura trying to open his mind to the darkness that exist in Sasuke, instead of making excuses for it or crying at the mere mention of it.
5. This relationship would develop with Sakura becoming closer to Naruto over time, and even really being someone who protects HIM. Lady GT had a couple of fake panels that really showed what this could of been at times, protecting Naruto from himself.
Now since I brought the legendary Lady GT in this, I should say she wasn't a follower of my "Sasuke should die in the end" idea.
More or less for the confession to matter it had to be a part of a growing and expanding character arc, that effected multiple characters. For whatever reason, or excuse if you prefer, that's not what happened. And instead it's now known as the fake confession. Maybe it is in canon. Who knows now? I haven't paid attention since the final chapters became canon.