This industry is already in its twilight — young people are unwilling to enter it.
Tips
history
From Ma Zhiyuan's (马致远) Yuan-dynasty 散曲 《天净沙·秋思》: 夕阳西下,断肠人在天涯 — 'The setting sun sinks in the west; the heartbroken traveler stands at the edge of the world.' One of the most beloved lines in Chinese poetry.
usage
Beyond the literal sunset, often metaphorical — used for declining industries (夕阳产业), aging populations, or someone in their twilight years.