What exactly do the other memories in the Animus Hub mean?

So in Assassin’s Creed Shadows, when the game begins we’re told that the Animus EGO will unlock the genetic memories of "your" ancestors. However, a hack then occurs, and instead we’re taken into the Animus Hub. There, beyond Shadows, we’re given the option to view memories such as those of Bayek or Kassandra. Does this mean that all the Assassins shown there are ancestors of the protagonist we play as in Shadows? Or were those additional memories made available because of the hack?

https://www.youtube.com/watch?v=eOKTZTA_DF8