Yes and no. While taking the Boon itself doesn't help to garner favor with our favorite primordial deity, opting to go through a Chaos Gate where you have to take a Boon offers you a chance to speak with Chaos and to offer Nectar or Ambrosia. Similar to the other deities in Hades, the only way to build a rapport with them is to opt for their Boon and offer up your gift. The boon will not inherently boost your favor but taking the opportunity as a way to gift will.