The essence of your comment is that paternity testing should be avoided because there is no benefit to children and there is potential harm to women. Your focus was not on the mandatory nature of any such testing.
And I believe you understand my analogy in spite of your faux confusion and outrage.
The benefit is to the "father", obviously, in confirming paternity or alerting him of infidelity and fraud. It's either peace of mind or potentially life-changing. The benefit is incalculable.
Your only arguments for why immediately post-birth is a poor time are that it would be convenient for everyone else (including the perpetrator of the fraud) if the victim was unaware and continued to be exploited for some time (how long? when would be a convenient time for the reveal?). That is outrageous.