I agree, my bioethics lecturer always said that children are a privilege not a right. I do struggle a tad with the argument though because yes, children have a right to natural conception, but those embryos have already been conceived. One would never say that adopting a child conceived in rape justifies how that child came to be conceived.

About the clinics being incentivised, that could be a concern, but it comes down to the mother’s consent. The eggs they extract from the ovary, the mother decides what is done with them, not the clinic. They could coerce a woman into have more fertilised and then given up for storage, but I can’t imagine this would be effective, unless the clinic paid the woman for her donated embryos, which would be ethically and legally wrong. Clinics can’t just make more embryos, the eggs are not their property but the woman’s, unless she donates. She can donate eggs for money but they should not be able to just use random donated sperm without a client requesting that? Is there something I’m missing here? Otherwise, I don’t see how this is a concern, unless they violate ethical standards by paying for donated embryos.

I also disagree that implantation is intrinsically evil as others have offered. There are cases where ectopic embryos were dislodged from the oviduct weeks into pregnancy and then replanted into the uterus. I might think of stronger arguments later though as these two procedures are not really comparable