This is a very interesting statement to consider when thinking about this excellent short story. Certainly we can tell from the beginning of the story that poverty is something that oppresses Jim and Della, as we see from Della's struggles to save any money at all and the way that what she has saved is so little:
One dollar and eighty-seven cents. That was all. And sixty cents of it was in pennies. Pennies saved one and two at a time by bulldozing the grocer and the vegetable man and the butcher until one's cheeks burned with the silent imputation of parsimony that such close dealing implied. Three times Della counted it. One dollar and eighty-seven cents. And the next day would be Christmas.
Note the way that the amount is repeated to stress the small amount of money that has been saved, in spite of so much hard work and shame has been endured. However, it is clear that the sacrifices that they make for each other give witness to the profound love that they have for each other. Although they are poor, we have enough evidence from the story to indicate that they are contented in their relationship with each other. What earns them the title of "Magi," according to the narrator, is the "wisdom" that they expressed, paradoxically through their foolishness, in the gifts that they gave each other and the self-sacrificial spirit that such gift-giving indicates.