"Usually children are only given up in grave, dysfunctional situations."
Not necessarily true. Oftentimes they're given up because the mother's made to believe, through cultural pressure, that she's in a grave dysfunctional situation when she just needs some help to get herself going. A teenaged mother will eventually turn twenty. A single mother usually gets married sooner or later. A poor mother could, potentially, get a job or get a better job or go to school for improved employment qualifications (and then get a better job). Most problems cited as reasons for child surrender are surmountable--but society doesn't want to be bothered helping mothers surmount them.
To say that all or nearly all mothers who relinquish are "dysfunctional" is to blame them for the relinquishment when they are not on an equal footing, power-wise, with society or the adoption industry, or potential adopters for that matter. The vast majority of them wouldn't even be relinquishing if they weren't terrified of failing as mothers--and that right there should tell you they were fit, if they'd just had the resources.