long-running TV/radio program
Refers to a television or radio show that has been broadcast continuously for many years. Often used with a nuance of respect or admiration for its longevity.
This long-running program has been on the air for 50 years.
人気番組 means 'popular program', focusing on current popularity, while 長寿番組 emphasizes the program's long history and continued broadcast.
Compound of 長寿 (longevity) and 番組 (program). The term is straightforward and modern, with no obscure historical derivation.