Some Devs argued that connecting exclusively to onion servers wont provide you extra privacy, the selected main onion server is good enough.
There's no explanation but maybe it's because your Electrum client will only sync with the server that you've selected, the "Connected nodes" are only for verification purposes.
If you manually select an onion node, your Electrum client will only connect to that one node and no other. If that server went offline, Electrum wouldn't automatically pick a random "normal server" to connect to. OP needs to ensure he unticks the "Select server automatically" option as well. So, if your main onion node goes offline, you go offline as well and you have no connection. In that case, OP needs to find a different onion node to connect to without touching clearnet nodes.
He's aiming for the "
Multiple server" option in the tutorial that removes the "
-1" arg which will enable Electrum to connect to other nodes (
servers).
Manual selection in the GUI is basically the same as that since there's no checkbox or menu that will enable "
oneserver".
Notice that in the 'Network' settings, there are "
Connected nodes" below, that's what the 'multiple servers' is about.
But as mentioned, even if connecting exclusively to onion servers is implemented, it'll not improve his privacy even further.
Additionally, using oneserver while connecting to other people's server is not as secure as using the multiple servers option.
