Given the history of idol singers in anime this really isn’t all that surprising.
In general I find the obsession with idol singers to be one of the more bizarre aspects of Japanese culture, and it is not one that translates well to a western audience.
I expect that this will enjoy success in Japan as the promotional opportunities alone will almost guarantee it. However successful does not equal good.
The question for me is not whether this will be bad, but whether the trainwreck will be sufficiently spectacular to be amusing in its own right?