The alternative to recycling newspaper and cardboard is chopping down forests and turning them into pulp, a process that also needs a lot more logistics, chemicals, energy, and of course forests that you have to re-plant.

Recycling newspaper is a no-brainer from a cost perspective. You can't recycle forever though, each time you lose some wood fibers that are too short and have to be removed from the recycled pulp, so you have to add fresh pulp.

Pretty much all paper manufacturers are now require to plant more trees than they cut down.

Burying old newspapers in the ground is a form of carbon sequestration. Really it comes down to what takes less energy: cutting down the trees, or the transport, sorting and reprocessing of old newspapers.

Upthread someone quoted a study that showed recycling newspaper used 60% of the energy compared to cutting down trees and making pulp.

So like I said, it's a no-brainer to recycle newspapers.