Obviously "lightweight" is a relative term.
However, a lightweight unit is MORE beneficial for extended travel than short in my eyes.
Im sure some could split hairs with regards to what defines extended travel and "expedition" travel. I know I could, and do.
As a true "expedition" has a start and a finish and/or a goal in mind, and my version of "extended travel" is more or less a form of "van life"
Which is an indefinite life "on the road" that may or may not have any pre-made plans.
Go where you want, stay where you want, on your schedule, and just LIVE. That's my end game plan. My paradise.
But regardless of REASON you are living out of your vehicle for a good duration,
it goes right back to overall efficiency and operating costs. When compared to a heavy unit, a lightweight unit effects the vehicle less.
It lessens the fuel consumption, maintenance, and overall wear and tear on the vehicle.
For example, just think about the tires. Anybody running a good Load E tire knows how much $$ they have wrapped up in tires.
Dropping from a 4,000-5,000lb unit to a 2,000-3,000 lb unit will do wonders to tire wear and tread life.
I think most would LOVE to get say, another 10-15,000 miles out of their tire investment.
And folks living on the road in a vehicle will be much more effected by overall operating costs.
So lower the operating costs by shedding weight, and lessen the financial burden to stay on the road.
And do not confuse a "heavy" camper with durability.
A lightweight camper built correctly can/will be just as durable as a heavier unit.