All true ... but ...
The fact is most over-landers spend about 80% or more on paved roads. But one can never quite know for sure what may be encountered. So skills are required ... even on a big bike.

Many on big comfortable GS's going two up avoid more technical sections. In some parts of the world that is possible, but not everywhere.

Riders go with the big bike for ON ROAD comfort, speed and two up ability. Simple. Different strokes.

Not everyone is looking to ride a Dakar event for a RTW ride.
I personally gave up on big bikes for travel and ride a DR650. But I ride solo and like to "explore" a bit of dirt. I also have 40 years off road experience riding and racing. Once again .... different strokes. But important to know your limitations.

Plenty try this. Many shit themselves and from that point on, AVOID all dirt tracks. Been there, seen it many times.

Even a fully loaded 650 can be a handful off road for a novice dirt rider ... seen many been put off dual sport riding all together from having bad, scary initial experiences. You want to start fun and easy to build confidence. This actually works and, IMHO, is critical to really learn and be safe.

For the average, unskilled rider, starting on a big bike is possibly dangerous, may lead to giving up ADV off roading all together (IMHO). Witnessed this many times among riding buddies who were convinced they could ride their big GS's off road and could just "pick up" skills required. They went back to street riding and ride ONLY PAVEMENT.

Broken Femur coming:

GS Rider Down!