I think we should differentiate between recreational camping and bugging out.

I'll assume that when you go camping you probably do it some time between spring and autumn. And you have every intention of returning home before winter when the temps get below freezing. Lightweight sleep systems are adequate for this.

But if you are preparing for a bug out situation, then you should be planning for the worst. And the worst means that you are forced to leave your home in the middle of a freezing winter. In this situation, I think going lightweight is inadequate. Could it be done? Yes. Would it be difficult? Hell yes.

I have a Eureka "Assault Outfitter 4" tent and a Slumberjack "Big Timber" -30F sleeping bag. Both are bulky and heavy (combined weight is 27 lbs). There's no way I can carry them on my back along with my other critical survival gear. So how do I plan to bug out with them?

I also have a Cabela's "Super Mag Hauler" deer cart, with the dual wheel kit added on for extra durability. This cart is made for hauling heavy game out of rough country. Hauling a tent and sleeping bag into rough country is no problem.