I used to work with teenagers, and a lot of them were adoptees - and they often spoke of feelings of being unwanted.
I made it a point to tell them about my own adopted nephews - how their birthmothers, rather than have an abortion, endured the discomfort of pregnancy and the pain of childbirth to bring them here, and how their adopted family waited and saved and prayed and begged and researched and hoped for them. Then I'd tell them how many of their non-adopted friends were oops babies anyway, and I'd end by saying, "trust me, you're the most wanted-ass kids in the whole world."
But there's more to adoption than just that. Adopting is actually really hard, and expensive, and difficult. Three of my nephews are adopted, and my brother and sister-in-law endured years of waiting, several false starts (when the birth mother changed her mind), and they were scammed on an adoption (to the tune of $20,000, in the early 2000s, so, you know, it was more money then). They ended up spending a lot of money and dealing with a lot of legal stuff.
Having a biological child, hard as that is, is infinitely easier, and even with fertility treatments, often a lot cheaper.
I'm so grateful my nephews finally joined our family, and I'm so grateful to their angel birth mothers for bringing them here.
The lady in the book you're reading sounds a bit batty, but even though I'm a 40 year old woman with fertility issues, I'm still going to try to have a biological child first - because adoption is HARD, even if there are more children who need homes than adoptive families ready to take them, it is STILL VERY DIFFICULT to adopt - take it from me, I've watched three adoptions first hand. Making a baby the old-fashioned way is infinitely easier.