Do phals have a finite life span?

[ALToronto]

An acquaintance has 3 very old phals, cornu-cervi or similar. They're badly in need of repotting, but I wonder if it's even worth the effort if the plants are on their last legs. The old stem is about 6" (15 cm) long, and there are 6-8 green and seemingly healthy leaves at the end. Lots of healthy aereal roots, but anything in the rotten medium is rotten as well.

Worth saving?