Makes sense to me. That is how expensive liability/labor is to “recreate” family bonds.
Although, the labor received via family bonds will greatly vary based on family, and time period. What was available before may not be available now due to different options becoming available for the aforementioned family members providing the labor.
Re. sexual abuse, RAINN says 34% of child sexual abuse is by a relative. Unless you're replying to GP, specifically saying "incest is more likely to happen in the family" (which is definitionally true, but vacuous), this appears to be mistaken.
I remain to be convinced re. physical abuse, particularly from other children, particularly given what I know of adult care homes.
Although, the labor received via family bonds will greatly vary based on family, and time period. What was available before may not be available now due to different options becoming available for the aforementioned family members providing the labor.