It's a bit like obsessing over the lightest frame possible. Yeah, we can get a 1lb frame made of space materials but at the end of the day it's basically something that will reduce a cyclist's average speed by like 0.1mph.
For anyone doing anything other than competitive cycling, comfort is far more important than anything else and fat wheel bikes with steel frames are damn comfortable to ride on.
A relatively heavy bike with giant wheels might take your average speed down .5 or even 1 mph. You almost certainly won't notice it.