That’s a good point! I think quality would matter even less when vodka is used with a mixer. Something like grapefruit juice is going to mask any off-flavors quite well.
The idea of flavor masking is often used in the snack industry. This is why so many chips are bbq flavor, especially if they are made from pea proteins or beans which are known for their off-flavors. Bbq is so strong it can cover up just about any bad flavor.