If parents CANNOT rather than WILL NOT parent their own children then adoption is acceptable, but not ideal. It is parents who will not that rob their children of their rights, wheter both parents or just one.
I have reservations about a child being raised by one or more biological parents who don't want the child.
Calling it a “right” is just muddying the waters though. It’s not a right, because a right is not dependent on the actions or inactions of others.