Many years ago, when I was studying biology (and Balboa was still sailing a rubber duck), my instructors told their classes never to cut paper with the instruments in the dissection kits. They said that most kinds of paper had clay in their sizing and that this clay would dull the edges of the surgical shears and scalpels very quickly. Is that true today? Are we writing on paper that is grinding our nibs to nubs?

As a corollary to that idea, these instructors also said that, when sharpening a scalpel, to finish the process by stropping the edge on the cardboard backing of a legal pad. This cardboard was said to contain a lot of clay sizing and would polish the edge to a razor sharpness. They were correct about that. I soaked some cardboard in water and had a look at the liquid with a microscope. There were lots of flat, plate-like particles in there, presumably harder than surgical steel. They put a fine finish on a blade.

Paddler

I've heard of people using their pens for decades, so I doubt that paper will grind the nib to a nub anytime soon. I do believe paper has an abrasive effect on nibs and that abrisiveness varies depending on paper type (ie: the brown paper bags vs. notebook paper). Cutting paper can dull a blade, but I think the dulling effect is more pronounced if you shear through a piece of paper as opposed to gliding on top of it.

I often use a simple notepad without the cardboard backing to strop my knives after honing them. If I really want to get a fine polish, I'll follow that up with a leather strop and buffing compound.

Some papers have a clay coating, which could conceivably dull a sharp edge. If the clay coated paper has greater hardness than uncoated paper, then that could account for the dulled cutting tools. I am not sure if the coating is abrasive, though.

Clay-coated paper is anyway not all that nice to write on with an FP, as it doesn't absorb the ink well. I always look for uncoated papers.

I don't even cut paper (any paper) with sewing shears, as it will dull them. So I'd imagine that's even more true for scalpels. But it would be much easier to dull a scalpel than to noticeably wear down a fountain pen nib.