I literally almost got an injury from using my iPhone 12 Pro Max while laying on the side on the bed for the last few years -- it's too heavy. I had to do various therapies to stop feeling pain. It's almost 230g and I also have an Urban Armor Gear case that adds a little bit.

iPhone Air is at 165g. I'll get ~72% of the weight and be able to comfortably use the device without getting tired.

Sample size of one and all that apply, of course.