Hi @martinzen,
Yes, the documentation is old and it’s not relevant to version 15. In Version 15, in lead, when you create a new lead, and if you want to link with Event then lead provides the ‘New Event’ feature and you can set it up. once you create a new Event, it’s linked with Lead. If an Email Account is created then will “Send an email reminder in the morning” according to the assigned person.
Thank You!