How to Hide/Remove Pages section in Menus (Dashboard)

You can actually hide Pages (and Posts, Custom Links, or Categories) using the Screen Options tab at the top of the WordPress Dashboard while on the Menus editor screen. Just open that Screen Options tab and uncheck the box corresponding to Pages.

If you want to make sure that option never gets checked again, you could then use the following code to prevent users with restricted roles from accessing the Screen Options tab:

function remove_screen_options_tab() {
    return current_user_can( 'manage_options' );
}
add_filter('screen_options_show_screen', 'remove_screen_options_tab');

Alternatively, you could add custom CSS to the WordPress dashboard to hide that specific class:

add_action('admin_head', 'wpse271824_custom_css');

function wpse271824_custom_css() {
  echo '<style>
    .nav-menu-meta #add-post-type-page {
       display: none;
    }
    .metabox-prefs label[for=add-post-type-page-hide] {
       display: none;
    }
  </style>';
}