The Archfey Warlock build in Baldur's Gate 3 focuses on disabling enemies instead of outright damage making this more of a support subclass.

All in all, it is fair to say that the archfey warlock is absolutely the weakest of the three options. Other than a few of its spell choices, it really has nothing to offer that can't be done ...

The Great Old One subclass’ new Level 3 feature lets players mix up their Warlock Spell so that it deals Psychic damage, and striking a pact with The Archfey now grants access to Misty Step.