Mint has been very clear about wanting to be a fan of idols, not an idol herself, for a very long time. It is at the very least preceding Niji going to shit, not sure if it also precedes her joining Niji at all.
Niji can be blamed for shattering the imagination of a massive Niji stan (she stanned it to hell and back during her first stint as Mint after all), but Mint's "I don't want to be an idol!" thing doesn't really have anything to do with them. That's Mint's personal brainworm which she'd have regardless.
It also doesn't really matter, since there are shittons of Holos who never planned to be idols and others who still don't aim in that direction.
Bluntly, the list of people who actually wanted to be idols from the start is smaller. Sora, AZKi, Aqua, Suisei, Kanata, Watame, Nene, Moona, Kiara, Gura, Fuwamoco, Irys, some I don't know enough to tell.
And with some, like Ame or Shiori, I think you can tell that they're still not that interested.
"I want to be a fan of idols, not an idol myself" is meaningless.