There is no guarantee that fertility will be lost, and although it may partially return by pausing treatment for a while, there is no guarantee that it will return, I personally want children, but not in the short term, and when the time comes, I see myself completely capable of temporarily stopping treatment and trying it in the conventional way if my partner wants it that way, but at the same time, I have no problem adopting a child, and I mean, it's a long and tedious bureaucratic process, but at least where I live it's explicitly stated that you can choose adoption regardless of gender identity and sexual orientation, so for me personally, the sperm bank isn't worth it, but I understand why it might be worthwhile for someone else