Bridget, there are few genuine orphans--in the sense that they don't have family anywhere.
There are people who think that:
-adoption is unethical (and should be illegal--at birth, foster, and/or in any form)
-giving a child up for adoption is unethical (some think it's unethical in all circumstances and some think it should be illegal)
-abortion is unethical (some believe in all circumstances it is unethical, including cases of rape, incest or when childbirth is possibly fatal to the mother)
-not using birth control to prevent unintended pregnancy is unethical
-placing a child in an orphanage is unethical
-abusing or neglecting a child is unethical (that parent is mentally ill is no excuse whatsoever, according to some)
-removing a child from their birth parent in any circumstances is unethical (that the parents need rapid rehabilitation while the children are in their custody)
-fostering a child is unethical (because the kids truly want to be with their genetic family, not with someone else's family)
-accepting monthly money subsidies for foster adoption is unethical
-abandoning one's child who has serious health issues or behavioral health issues is unethical
-infertility treatment is unethical
-having "too many" children is unethical
-having children you can't afford to support adequately entirely on your own without help is unethical
-a birth (genetic) father abandoning his child (to poverty) is unethical
-not abstaining from sex to eliminate pregnancy risk is unethical
-raising children in poverty is unethical (even if the poverty was the result of catastrophic events that occurred later)
-adopting a child and removing him/her from their native culture is unethical
-charging potential adoptive parents (loads of) money to adopt is unethical
-money changing hands in adoption is unethical
-being desperate enough to pay for a child is unethical
-dropping a baby off at a "baby box" or "safe haven" is unethical (some think no matter what the reason)
-having more children after giving a child up for adoption is unethical
-not paying child support, no matter what the circumstances, is unethical
-using society's help such as WIC, welfare, public housing or food stamps is unethical
-relatives not supporting pregnant relatives is unethical
-fathering children serially (ten kids by ten different mothers, supporting only some or none) is unethical
-fathers abandoning first kids but supporting subsequent offspring is unethical
-raising a sibling's child or a grandchild and having the child call you "mom" or "dad" is unethical
etc., etc., etc.....
People also have double standards. They may say OTHER PEOPLE should adopt or sponsor children who have serious and/or complicated medical problems and/or neurologic or behavioral issues and are in orphanages, but they certainly don't take those kids in themselves. They may say YOU should be satisfied subsidizing someone else's children rather than raising a child yourself, but they do not forego raising children themselves and sponsor someone else's children instead.
The beliefs listed above may not be my own, but some claim them as their beliefs. Some people believe that if a person is infertile (from cancer treatments, for example) or a child gets leukemia or dies of some disease, it's ultimately "the Lord's will".
The only truly, truly ethical way might be in the very, very rare cases wherein a child has no genetic family whatsoever on the earth. Foster children, in reality, want to be with their own genetic family, as do adopted children, even foster children who are "special needs"-- kids who are chronically ill or came from abuse and/or neglect. Most people do not have the financial resources or the strong professional support needed to foster or adopt or sponsor children with serious, ongoing behavioral or health issues, but may suggest YOU do it. So many things are considered unethical...by some people somewhere. Everyone has their own core beliefs.
To send an older child across the world to a foreign country where the adopters don't speak his or her language...to be told that this woman you don't really know is your "Mama" (you might understand that word) while knowing that you have a "Mama" back in your home country whom you lived with for a few/several years and love..(maybe you were taken away from her because of abuse, neglect, or abandoned, but you want to go home). You may have had a foster mother for a long time in an orphanage and become very attached to her. You wouldn't understand what the people around you were saying. They'd put food in front of you, you'd perhaps never seen before. They would send you to school and the kids there might think you were strange because you didn't understand their words or culture.