See while it might not be THE most kino, I can't deny how absurdly high it is on the scale. I personally like it because it was Yoko Taro trying something new.
He was always killing his characters off and making grim dark endings up to this point. So this is him basically saying "fuck it why don't we just have a happy ending for once? I'll make it bittersweet at most."
This, combined with the fact that you have to fight him and the staff for a happy ending, is him ultimately BTFOing people who always complain about him making dark endings.
That alone makes it kino as fuck.