At least with Wacom tablets, the tip is replaceable, so there isn't really a problem. I've got through maybe three or four in about ten years, and one replacement tablet surface.
Honestly those tips last for ever you will most likely loose the pen or upgrade before you need a new tip.
We had one Intuos 3 pen die in the office because someone kept chewing on the end. A different one survived being being put in a mug of coffee instead of its little pen holder (user half-asleep from not having drunk the coffee yet, I suppose). My A5 Intuos 2 is still working well after ten years, with just a spray of foam-clean every now and again to keep it nice and clean.