I think my wife is too obsessed with hygiene and is overprotective of our daughter. How do I tell her to be more carefree?

As a mother, I will make sure the hygiene level in the house and outside is acceptable as the germs will cause children to fall sick easily. However, overly doing it might deprive their childhood, e.g. kids afraid of playing sands at beach and dare not to try out new things as has been over-protected by parents, don't know how to handle bullies by themselves and etc. Thus, I would suggest to strike a balance to let kids to explore themselves and learn through mistakes. You can talk to your wife and point out what are the areas that can be improved together. Remember do not use blaming during the discussion.