You're standing on a false premise, by trying to be stuck on the word "orphanages"; because reading the rest of your post, it would seem that there are no more children to adopt.
Orphanages have just been renamed as Foster homes.
Let's take this from the top. First, there are considerably fewer children requiring adoption. The second thing is a foster home is not the same as an orphanage. Comparing an orphanage to a foster home is like comparing a Federal prison to a half-way house.
Families take in foster children and the children live a relatively normal life. They go to school with children from "regular" families. They are in a regular life, meaning teachers, neighbors, etc. see them and observe their conditions. (Are they dressed like other children? Do they look and act "normal"? Do they have toys and other belongings like the other children?)
All those observations aid others in determining the child's living conditions. In other words adults and other children can observe and possibly detect if abuse is happening in the foster home just by listening to casual conversation.
Contrast that to an orphanage where all the children are confined together. Just as we would be more inclined to know what transpires in a half-way house as opposed to a prison, by observing and possibly having conversations with someone in a half-way house, the same applies to children in a foster home vis-a-vis an orphanage.
The abuse in orphanages proliferated due to the children being unable to inform the general population.
Where are the abuse stat's, apple?
Do a Google. You'll see all the abuse stats you'll want.
An orphanage is not the same as a foster home. Before abortions were legal there were too many children to be placed in foster homes, thus, they were institutionalized in orphanages. No one cared about them. They were out of sight and the only people they could inform regarding the abuse were people complicit in it.
So, I ask again, "What would change if we returned to the days when abortion was illegal and we were flooded with unwanted children?"
If you believe the same abuse as in the past would not reoccur, tell me why. What would change or what has changed?
If anything, we're a more selfish, self-centered society than we were 50 or so years ago. Spoiled. Believe we're entitled. Do you really believe we're going to care more about children we can not see due to their being in institutions?
You must have something on which you base your beliefs. I'd like to hear it.