Each user role in Canvas courses is assigned specific permissions. Generally these permissions are set up by the Canvas administrator for your institution.
The ability to view other users' email addresses on the People menu is controlled by a permission called Users - view primary email address. By default, students in Canvas have this permission disabled; refer to the Canvas Course Role Permissions resource document for information about the default roles and permissions in Canvas.
You mentioned, "I am not able to see his email as we could in Sakai," which makes me wonder if your institution changed LMS systems. If so, it might be worth asking your Canvas admin to see if this permission can be turned on.