Admittedly, as a European, this whole idol system is very foreign to me. But the idol concept is now the central plot element in a large number of anime. Thus, this anime, even if not completely authentic in all its elements, should portray the system quite accurately.
And what can I say? It's hollow, it's empty. Two young men who have no talent of their own, can only sing mediocrely, hopping around on stage and grinning borderline idiotically into the camera. It's the promotion of a soulless business. Essentially, all of the series' protagonists are portrayed as people with very limited worldviews. Some want to be worshipped (for virtually no achievement), others desperately want to be worshipped.
The protagonist, at least at the beginning, stood out, honestly demonstrating what it's all about: making money without much effort. But over the course of the series, he naturally had to be "converted." And mutate into a greased cog in the machine.
Even this soulless stuff could have been packaged appropriately and appealingly. But the series - thankfully with 10 fewer episodes than usual, but still far too many - never manages to, and never even attempts to, offer real substance. The little content per episode is even stretched out by mostly mediocre to bad singing numbers.
In the end, the series is like the idol system itself: without substance, without soul, without a reason to exist. Bad entertainment designed to rip people off. Visually, the whole thing is also nothing special. From the character design to the animation, this is a truly cheap production. Inside and out.