Like it is in WoW
In WoW too, 1v1 isn't the balance focus of the PvP team, and nobody cares, it's always fun to duel people before an event or while waiting in a queue, or just to test a build or confront a friend just for fun
It wouldn't harm the game in any way
I don't understand why this isn't a thing after all these years
And yes I know you can create a custom lobby and blablabla...But come on...