Remaining logged in lets anyone who sits at your workstation know your Nostr identity by visiting NostrNests.
This defeats the purpose of having a pseudonymous protocol, since any search of your computer -- even if you have your Nostr keys in cold storage and only ever logged in using private browsing -- will identify you. You'll also have all those public unencrypted NostrNests advertisements you posted sitting in public folders on multiple servers to cryptographically confirm your Nostr npub really was the computer's operator.