A full archival node helps the network because you can help bootstrap other nodes that are syncing to the network, similar to seeding files in the bit-torrent network.
If you don't use your node for transactions, you are not getting any benefits personally. More importantly, in case of a user activated soft, or hard fork, your node would not be able to be an enforcer, because you are not running your BTC through it; you would simply be at the behest of whatever other full node you are connecting to. So, if you are already running a full node, might as well connect to it too.
Does this somehow still helps the network? Is my contribution to the network meaningfull?
Not really. A full node's primary purpose is to help you, the node maintainer, to trustlessly check your bitcoin balances and to retain a higher level of privacy on the network. Other nodes don't trust your node in the first place, so it doesn't really benefit the network to have another node in there.
You don't need any balance on your node btw, you can simply connect your hardware wallet to it, then it becomes useful to you. And then the network benefits directly from another sovereign peer :)
If you don't use your node for personal transactions, it has effectively no impact on the network.
The network doesn't detect rogue nodes; it doesn't care what other nodes do. Full nodes only accept valid data; they'll ignore whatever rogue data others send.
Don't just run a full node. USE one.
I know this advice is meant well, but it leads to nonsense like people running a 1000 nodes on AWS and not looking at them. If they don't affect anyone's financials, they're just spinning rust.
Summary: There is a scammer impersonating Mr. Leon Li (Huobi CEO) to ask me to invest 1 BTC in order to receive 2 BTC per week. This scammer's Facebook is in the top of Google search because the Huobi CEO does not publicize his personal Facebook. The scammer also video called me and play a muted video of Leon Li for a few seconds and said there is a problem with the connection to make me into believing him. And here is the story of how I "tricked" this scammer lol
I have long been annoyed with scammers because every now and then I get scam/spam calls. I used the Page Editor extension on Chrome to create some screenshots to convince the scammer that I transferred 1 BTC to him but was blocked by Binance because of the high risk. To verify, the scammer needs to transfer 0.001 BTC ($31) back to that wallet. So he really did it haha
Then I processed to ask him to send another 0.01 BTC (310 USD) with the reason that the risk is now escalated. But it wasn't success. Let me know how to improve next time.
Edit: You should do this too. Very entertaining and satisfy once you can scam them back haha. If everyone of us do this, the scamming industry will take a big hit.