ALSO, what is the obsession with embodied energy?

Like lets think about plastic bags from an object use standpoint. Given you have a collection of stuff to carry would you prefer:

A) A reasonably sturdy bag that can be styled to your preference (like with art or whatever) that you have to remember to bring with you when you need.

B) The literal minimum possible material to be considered a bag. Even money whatever you put into it will punch straight through the bottom, or you'll need to use 2-4 nested bags anyway. And it'll be uncomfortable to hold the whole time.

I think from an object use perspective a reusable bag is more pleasant to use.

But embodied energy calculations are convenient because you can get numbers to compare. But it ignores externalities.

Like if you actually considered the embodied energy of the median tote bag vs the median plastic bag from the point that it was extracted from the ground to the point that it returns to dust, I think the story would look really different. I'll bet a sizable percentage of plastic bags don't even make it through their first use. Meanwhile I've got tote bags that I think are fully 15 years old. Plus if you consider the remediation future generations will need to do for plastic bags. meanwhile I can actually bury a cotton tote bag in the dirt to decompose and it doesn't need infrastructure to prevent poisoning the water supply.

Did the authors consider the embodied energy of the landfill itself? Shipping? Trash collection? Ongoing monitoring? The embodied energy of the future carbon capture system?

It's just so convenient to look only at the materials, equate that to kg of co2, and use that for whatever narrative makes you feel good.

As somebody who cycles as a primary form of transport, I prefer plastic. It weighs less, it's more compact, and it's waterproof (important when it's raining). If I had to use cotton that would incentivize using a car instead. It's not a huge difference, but it doesn't take many marginal cyclists switching to cars to wipe out all the theoretical environmental benefits of cotton.