one-click unsubscribe for Gmail

Hi,

Starting February 2024, Gmail will require the following for senders who send 5,000 or more messages a day to Gmail accounts: Authenticate outgoing email, avoid sending unwanted or unsolicited email, and make it easy for recipients to unsubscribe.

Add List-Unsubscribe header to outbound campaign emails (default)

I enabled the option, but the display does not change in e-mail.

I want to know why.