To be fair, Auti was the most consistent player on that roster. And even after it fell apart he continued to be consistent on both AWP and Rifle.
Auti left because NA CS became (is) a joke. VAL just made sense for any decent NA player to leave.
Him coming back is proof that NA CS might just survive the VALORANT migration. Him and Nitr0 coming back is a huge win for the NA CS scene.