Aside from the blatantly obvious yet ignored due to marketing fact that you're drinking a liquid designed and made for calves.
Most ppl would never even consider drinking human breast milk thats at LEAST designed for humans, let alone monkey giraffe or dogs milk...
Milk is made for babies, not adults and the vast majority of the population stops producing the lactase enzyme that makes milk digestion in infants possible. So in many respects adults are to some degree lactose intolerant.
Lactase persistence - Wikipedia
6 in 10 Adults Can't Digest Milk
On top of that there is many studies lately that indicate milk causes weaker bones especially in women amd can lead to prostate cancer in men.
There's also the mass amounts of hormones and antibiotics that go into dairy cows that I think anyone who finds out about them simply wouldnt want to ingest. Especially not daily.
Why Is Milk Consumption Associated with More Bone Fractures? | NutritionFacts.org
Does Milk Lead to Prostate Cancer? | The Truth About Cancer
On a personal level I noticed less bloating and torso "fullness" after stopping dairy and just generally lighter in the gym. I know several ppl men and women who had nuisance skin conditions clear up rapidly as well.
Dont get me wrong dairy is delicious and I used to love it, also being an easy tasty protein source but quality of protein has been simply more effective than quantity.
That said I hate ranting and I'm not a fanatic, I eat pizza and lasagna and butter but definitely cut out 90% of the dairy amd feel about 90% better.
Try it out..