You always have to maintain confidentiality in crypto investments otherwise you can be in danger, because you are the only one who can tell people about your investments and create your own danger,
Security must not be an after thought in crypto but should be first and foremost preference. There are many technical measures which are already discussed here but one thing which most of us ignore is the point highlighted by you which is never disclose you real wealth to public. Hackers technical attack is secondary thing, first they have to find out the real target and if you are disclosing your real worth then you have done half of the work for the hacker.