You do know pretty much any drink besides coffee and water is sugary and acidic. Soda? Sugary and acidic. Milk? Same. Fruit juice? Same. Soda? Same. Booze? Same. Do you know which one of the drinks I just listed has ANY nutritional value beyond the sugar and acid? Milk and fruit juice. Milk has calcium, vitamin c, vitamin d, protein, fat, and carbs. Milk is incredibly calory dense. Fruit juice only has vitamin c and maybe antoxidants if you buy the right one.
With any food, unless you have bad genes, Moderation is key. Milk isn’t bad for you if you drink a glass or two a day or you have lactose intolerance.