Why is Weight The Only Solution Being Offered To The Problem Of Traction?

[BubbaLouie]

We have one member here who preaches the gospel of weight: Tractor Sizing - TRACTOR WEIGHT as ONE (1) CRITERION in TRACTOR SELECTION

My question is why aren't other alternatives being considered by the industry like this one:

My experience is in this order: weight, 4WD, ag tires, engine power.
You can get weight various ways such as tractor weight, fluid in the tires, front and or rear cast iron weights, for example.