From one study I read that is not true. People have looked at the lifespan of Eunuchs in the Korean court and found they lived on average 14 to 19 years longer than their comparable non castrated counterparts. Here is the study.
Maybe women with no exposure to estrogen?
The fact a male may need testosterone for some mental developmental aspects would not mean a female may need it. Just like a male doesn’t need the same amount of estrogen to develop.