Is it mostly aesthetic damage?

I find it hard to believe NASA didn’t think of everything.

There is a risk that partial splits of the wheel could damage the rover's wiring, but they have a cunning plan to rip the affected part off before it can cause damage. The stongest part of the wheel would survive (the central rim) they could drive on that for years

They did think of everything they and everyone else knew at the time, but Mars rocks were more embedded in this part of Mars compared to those seen before. It was designed to last 2 Earth years, it's been running for 14, so all is good. It'll run for many more years :)

I recall when the first holes appeared in these wheels, all the doomsayers were telling the world its be unable to drive etc etc... that was a decade ago, and it is still roving, and climbing a mountain :)