Our paper folders are substantial. Are they as sturdy as a plastic folders? Of course not, and that's great because plastic folders last literally forever.
Additionally, dark +/or brightly colored paper folders are not considered "desirable" in terms of recyclability, increasing the likelihood that they'll pass through wish-cycling bins (recycling), and end up as landfill.
Beyond not lasting for eternity, Wisdom folders are not just recyclable, they're highly recyclable by design.