There’s a downside to carrying a cellphone - at least, one with the battery charged and in place: you can be found. Assuming he cellular network is still up, you might want to make a call when you first set out. After that, depending upon the circumstances, it could be a risk.
Recall that this load-out is intended for a three day )five, if you stretch it) on-foot E&E to get back home or to some other point of relative safety. An extended field stay is is another matter altogether.
If you are fleeing an oppressive government (or escaping the law because you are a criminal) that would be true. If your bug-out kit is being used to escape a hurricane, a wildfire, civil unrest then it could mean the difference in life or death. In the former case, throw the phone in the back of a moving vehicle.
I think it's a mistake to prepare your evac kit for one situation only.
