I vehemently disagree, the case is that there's financial incentive for the adults around her to have her continue to stay within this industry, and children's passions are usually aligned with what provides them security and acceptance from the adults around them, we impart values to our children, that's how humans work. The fact that now she is finding self-worth in "ganbatte" good intentions, which are themselves a goad to continue this stressful activity, but isn't an indication of agency or choice either, it's merely an extension of the fact that she defines herself by these implanted expectations.
The fact is that society has a blind spot for this form of exploitation because it's beneath a veneer of the glamour of celebrity. If this is allowed then why not manual labour? Don't the children yearn for the mines? Well, give them their autonomy.
I won't claim your points are invalid when it comes to child exploitation in the entertainment industry, but there is a reason I specifically mentioned this being a work of fiction. Whatever the reality of a child's capacity for consent and autonomy with regards to entering any kind of professional field, the fact is that
in this story we have been repeatedly told- both by word and visual- that Oura is genuinely passionate about her work. The primary conflict is not that she's being taken advantage of, nor that she is being forced to take part in the business. It isn't that kind of story.
This is a story about a boy and a girl, where their relationship helps the girl balance her work and personal life while the boy learns to be more confident and assertive out of a desire to help her. The conflict is the struggle for the girl to balance the two sides of her life, made worse by a mother who doesn't realize she's been spending too much time acting as a manager and not enough time acting as a mother. It is not a dark critique of the entertainment industry; that's Oshi no Ko. It's a fluffy romcom with sprinkles of drama.
Beyond that and the debates of child autonomy, said mother has never been shown to be financially motivated. She's always been shown prioritizing her daughter's
career and
success, but never concerned with the money. By all indications she's an unintentional stage mom; doing her best to ensure her daughter succeeds in her career, without realizing that she's been emotionally neglecting her daughter.
And on that note, there's something else we both forgot. Despite the cutesy art style and awkward fluffy interactions,
these are high schoolers. More than that, they are at the very least in their second years. That means they're both 16-17 years old. Old enough that their autonomy is no longer a question; in most countries they're old enough to drive, and in some they're old enough
to get married. Not quite adults, no, but certainly not young children incapable of making informed decisions on their own.