Kishi kinda added fuel to the flame of the Sakura haters after having her absent for so long, and then make an appearance only to stress a point (Yes I assume he wants us all aware of Naruto potentially deteriorating in power as a result of his giving out chakra) that is probably obvious to a lot of readers. On top of that, in this particular chapter everyone was hoping to see more of Madara and Hashirama and gang. It's like he used her as a commercial. In my opinion, it was just bad timing. He should have used someone else to say that, anyone but her, because we know anyone else wouldn't be subjected to such hate after making the appearance and statements she did.
On another note, it's completely natural to be concerned, and they are young teens who have never experienced war prior to this one. Also, she is a medical nin. It's kinda her job to stay on the sideline. But come on Kishi lol.
