Blizzard Reveals When Overwatch 2 Loot Boxes Will End - IGN
Blizzard has announced when loot boxes will be phased out of Overwatch in anticipation of the new Battle Pass system.
However, the post notes that you'll still be able to earn standard loot boxes after the Remix event.In fact, Blizzard confirmed that all unopened loot boxes in Overwatch will automatically open before the launch of Overwatch 2.