I too find this a difficult one. On the one hand, I do not wish for decent men to be discriminated against, and for childcare to be seen solely as "women's work".
On the other hand, children are far, far more likely to be sexually abused by men than by women. And paedophiles have been shown to go to extraordinary lengths to be close to children.
I think the point some PPs are making about any concerns being ridiculous, as kids have male coaches, school teachers, music tutors, etc, is not a valid one. Because these are all school-aged children, who can be taught some awareness of the PANTS rule etc and have the language to be able to speak out about any wrongdoing.
Whereas infants, toddlers and pre-schoolers are mostly too young to understand privacy and bodily autonomy, and too young to be able to report secual abuse. So the nursery age-group is far more vulnerable to sexual abuse than are school-aged children.