PVC cable jacketing longevity?

That makes sense. Incorrectly installed NM will probably last lots longer then expected (unless water wicks up into the paper, in a location with freeze/thaw cycles), but properly installed UF will last much longer.
I recently pulled out some underground PVC ( just before things froze up) that had 14/2 NM cable in it.

Original install from when house was built in ‘83.

The sheath was nearly as white as the day it was put in. All writing clearly legible and in fine working order.

It was buried under a driveway about 4” below the slab.

I feel that just regular NM ( Romex) from 40 years ago had a more solid outer sheath than todays and seems better constructed
 
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