That's literally how you could assume it's good for you but there are also plenty of studies that support the assumption. Plenty show that low-fat or non-fat yogurt and milk are "good" for you.

Humans have been milking everything they can get their hands on since prehistoric times. There are a number of reasons to not eat/drink those things (taste, vegan, intolerance, etc) but that doesn't suddenly make yogurt, milk, and cheese "bad" for you.

https://www.hsph.harvard.edu/nutritionsource/food-features/y...