if you have access to creating components, you can use this CSS to hide it if you think it’s really necessary. although if you are just a moderator and can see emails, but don’t have admin access to update your Discourse, you won’t be able to do it. depending on your browser version, you can use a script tool extension like stylus to make css customizations to your pages.
dt.email {
display: none!important;
}
dd.email {
display: none!important;
}