When you are not logged in, you cannot use the tools in Help -> Licensing such as the tools to fetch an updated copy of your license.
When you are not logged in, you cannot use the Add-On Explorer to install or remove toolboxes.
If you are using a fairly new version of MATLAB, but not the newest released version, and you are not logged in, you might not be able to use doc . These days, doc creates a browser to access documentation on the MATLAB site, but if you are not logged in, it cannot check to see whether you are entitled to access the old documentation. There is a preference about whether to look online or not; see https://www.mathworks.com/help/matlab/matlab_env/help-preferences.html
If you are not logged in, MATLAB cannot check whether to tell you about new releases being available.
