User manager with 2 capabilities:
– list_users,
– edit_users
does not see ‘Capabilities’ link under user role. It’s enough to open user profile to change a role(s) granted to user.
It’s possible to hide from such user manager a primary role controls using URE custom filter, like this:

add_filter('ure_users_select_primary_role', 'my_users_select_primary_role', 10, 1);
function my_users_select_primary_role($select) {

    $select = false;
    return $select;

This filter does not take effect for site superadmin.

You may add this code to the active theme functions.php file or setup it as a Must Use plugin.