It lists VPN, Proxy, Tor, etc. Presumably a minus sign in a circle means you don't have the thing?

I had same confusion for a second but the html does clear it up: yes, it means you don't have the thing.

   <li class="...">
     <div class="...">
       <div class="..."></div>
     </div>
     <span class="text-sm">Residential Proxy</span>
     <span class="sr-only">Not detected</span>
   </li>