Happened at my daughter’s and Son-in-law’s apartment:
The whole building was plumbed with CPVC, from back in the early 80’s.
All the apartments had to be re plumbed because of leaks..............
https://www.clickorlando.com/news/plumbers-warn-of-cpvc-piping-problems_20151105190735671
Yea, anyone with common sense would know that CPCV was NOT going to hold up against hot water and would turn brittle.
Oh well...that’s why I don’t trust new-fangled ideas when it comes to plumbing. Give me copper, or give me (whatever)!