Fans of Netflix's Mindhunter have finally been told that the series isn't returning -- years after it ended. But the writing was on the wall before that. First there was the long silence after Season 2, then the news that the cast had been released from their contracts because the series was on "indefinite hold." Letting all of a show's actors move on to other opportunities is a death knell; just ask the stars of All Rise. Plus the use of the term indefinite made very clear it wasn't in anyone's immediate future.
Source:https://www.cbr.com/mindhunter-season3-canceled-best/