Do they anticipate lots of future willing surrogates?
Putting the moral issues of vessel-using aside, surely there aren’t many women who are both willing and able?
There is no way I would risk another pregnancy, especially not for a child I wouldn’t keep. Perhaps at one point I would’ve been willing to do it for my sister, but my own kids took such a toll on my own health (and the well-being of the entire family while I was incapacitated/recovering) there is no way I would agree to it now.
Plus yes, anyone that had puberty blockers and then cross sex hormones will have no viable gametes to store anyway.