I agree about everything. Yet, just because she CAN learn to face it doesn't mean she WILL and it's not a risk-free try. If she fails she will destroy a childs life and through this also negatively effect many others, that's why becoming kids is the most important question/decision of your whole life and this woman has clearly not done it for the right reasons (we don't know why and that's not important for this matter).

As someone being raised by parents that realized they don't want to be parents but "tried their best anyway" I can say that I prefered them having a realization about this and giving me to someone who actually wanted to raise children. I was really jealous of one of my my classmates family and his life and he wasn't their biological son which everyone could see without even asking.
Unconditional love and care is great task that cannot be achieved if you aren't in for it with 100%.

Maybe she will grow with the task without hurting the kid in the process and everything will be alright but it's hard to say "you HAVE to try it/gamble!!!" without thinking about the kid.
It's about the kid having a good life not the mother feeling good about herself imho