Thank you. I hadn't been on this forum for the past couple of years, but I remember that in the past you had given me some very valuable information. It was the LN instructor I mentioned that suggested to use only one node and recommended a couple of them in particular. His point was that that some nodes in the crowd might be a bit dodgy, and that using one node only is slightly better in terms of anonimity. I guess I'll follow your advice, but I'd like to hear your comments, if any, on his take.
P.S. I hope this post gets accepted - my previous reply got me a warning from a moderator which I wasn't able to understand for lack of familiarity with the terminology.
Electrum relies on servers for blockchain data but it does not trust them. They are run by random volunteers and cannot be trusted. Getting data from multiple servers and cross checking it is better than relying on any one server. The exception to this rule is if you are running your own server in which case you have a copy of the blockchain locally and don't need to trust anyone else.