People reading this should probably know about Arashi. SMAP is big time but Arashi is REALLY entrenched in Japanese media. They have their own game show, which is quite fun to watch, they appear in TV and films frequently. They are in many ways better, songs more catchy. Every member of SMAP is talented in some way but they aren't all good singers despite their popularity in music and culture. In fact, Japan is interesting in it's almost a kind of known joke that some member's of SMAP singing and dancing kind of sucks. Every band usually has a weak link on board but it never really matters. People are drawn to the frenzy, the popularity and enjoy sharing the enthusiasm for what it is.
I thought SMAP had a young version, ready to graduate into the real SMAP as the core members slowly got too old, so that the brand could live on, similarly to how Morning Musume are still around as a brand, though none of the original cast is present.
We always joke at work that the interns get younger every year. They don't, we all get older. But with MoMusu, they really do get younger every year.
I always wondered about the business model. As a high school student, I didn't have money to buy albums or go to concerts. As an adult, I do. But I'm not going to go see a group of 12-year-olds perform.
I think that once your original lineup has reached its thirties without being replaced, you've basically declared that you're not going to be taking the Morning Musume approach.
The quote in the article is hyperbole. It's not unlike fans of *NSYNC or whatever other boy band you might know--there are super fans who indulge in the drama. Also, television personalities in Japan begin to feel like part of the family, as the bangumi format encourages a sense of hanging out together on a regular basis. SMAP is very much a part of the family, so to speak.
