There is currently a “user directory” plugin with limited, but valuable functionality. See this thread:
https://meta.discourse.org/t/discourseuserdirectory-experimental-user-directory-plugin/4301
And here is the GitHub:
https://github.com/www2014/discourse_user_directory
I’m also attaching two screen shots so that you can see what it looks like. Remember that you have to add a new link to your menu:
And here is what the main directory page looks like: