I do think that matters here. Since oil is pure fat and sour cream is not, you’re already changing the recipe quite a bit. Full-fat sour cream helps replace some of that richness and gives the cake a better texture.
If you use light sour cream or fat-free sour cream, the result will probably be less tender and potentially a little gummy. Greek yogurt could work in a pinch too, but it tends to be even thicker and tangier, so I’d loosen it with 1 to 2 tablespoons of milk
