I apologize for always bringing up trans stuff in genderswap comment sections, but I really do think this manga is... like, it feels like the author is processing some of their own yearnings. So the story is less about the actual genderswap and more wish fulfillment fantasy. I dunno, I don't like speculating too hard about an author's state of mind but that's the vibe I get from this manga. If you're not already really excited by the idea of experiencing being a female idol (through a PoV character) this manga probably won't do much for you except just be cute. Which is OK!
I also think this chapter's joke is already outdated. In the currently ongoing vtuber boom, anyone CAN in theory become an idol now. It's a brave new world.