What has happened to exclude contacts option in Campaigns?

What has happened to exclude contacts option in Campaigns?

Until very recently, we were  able to exclude contacts from campaigns - see picture from our learn documentation 👇



This option is no longer there:


Use case is when someone registers for an event there is a workflow where they are tagged for the event in CRM and a flow to add them to the Exclude list so that they do not keep receiving campaigns promoting the event. Can anyone tell me why this has gone and what the steps are to now do this? Many thanks