zb13
Member
I don’t think the intent of those of us who have done the trek was to discourage you from taking something better than your phone, it was just to set reasonable expectations so that you could take a kit that allows you to make better pictures than with your phone, but not at the expense of your safety or health on the trek. I’ve done many multiple day treks in the Himalaya, the Alps, the Rockies, and Patagonia, and lighter and simpler has served me well. I’ve also seen many people carry too much and not be able to complete the trek (occasionally with some rather serious outcomes).
One other reason I’d discourage just the phone - you often don’t have a lot of choice on where you are able to position yourself (for example - you might have a big drop off on one side and a cliff face on the other, or you may be surrounded by people’s homes and fields, or your guides just don’t want you wandering off). The short telephoto range is pretty important.
I think one other great lesson I’ve learned over many treks is: I’d rather take something like the 24-200 with all it’s limitations and use it and feel good trekking, than take a bunch of higher quality equipment and not use it as much because I’m miserable due to the weight (or worse, I’ve just stopped carrying it and put it in the bag the porters carry). If you are open to renting, the 24-70 f4, 24-120, or 24-200 are all good options, and it you want to drop some weight on the body, renting a z5/6/7 series camera would help a bit as well. One camera and one lens is pretty easy to fit in most day packs and still have room for all the clothing, water, first aid kit, etc. that keep you safe and comfortable.
my knee jerk response is the 24-120. it’s sharp, flexible, reliable and light 
