Could someone explain to noobish me what remote staking means or how it works?
Somehow the entity who has access to the private key needs to be connected to the internet, right? So what is the alternative to keeping the wallet open?
It's explained in the NEM FAQ
https://www.nem.io/faq.html#howDelegateHarvestBasically you are lending your staking power to another account, preferably with an empty wallet.
First you generate a key with your original wallet, which is only used for staking and activate remote staking. (This key has nothing to do with with your funds and private key.)
Then you can close your original wallet and put this key in the config of another wallet, which is and stays empty.
The empty wallet stays open for staking and all rewards are going to the original wallet.
The benefit of this setup is, that the wallet with your funds is only needed when starting remote staking and afterwards it can stay offline.
If the server with your staking wallet gets compromised, in the worst case, the staking key gets stolen and then the attacker can stake for your wallet
This architecture in connection with trezor would be a very secure setup.
Ok I see. This would also solve the problem for people using the mobile wallet, which is not going to stake coins to not surge the battery! I'm sure you are welcome to come to Slack and discuss this with devs. Check out #ideas_features over there, or go to Github and file a feature request.
On the downside, it could result in many people staking on just a few big servers, and only those servers running the actual network, which is not generally desirable because it makes the network less robust...