I can't say that I agree with that, and again, I say this coming from a 6, which was one of the lightest iPhones. No offense, but I don't understand how anyone finds something that weights 200g tiring to hold.
The funny thing is, it's only 30g heavier than the X, and the X actually feels heavier to me because it's denser/thicker.
No offense taken.
Holding it one handed (like while reading news or browsing forums ) with the little finger under the bottom of the phone gets old kinda quickly for me. I used one for a while and instead went with the X. I had a 7 Plus previously.
Out of the most current batch of iPhones (7, 7 Plus, 8, 8 Plus and X) the 8 Plus is the heaviest