It could be semi-transparent, i.e. visible to members only.
And there are many types of insurance where privacy is not a concern. For example, pet insurance.
For some types of insurance, such as car damage, most of the info is in public databases anyway.
i think there is no need of anonomity in insurance field also also decentralzation can't make enable to invest others money in something. I don't get idea about how this can work. P2P insurance