As written by the earlier responses, virtually everyone has said from their own experiences that they've become more healthy once they have stopped or reduced their consumption of dairy. It just makes sense, we need milk once in our lives from birth until the end of weaning, and that is our mothers milk. Of course, there are populations around the world that consume dairy, but all successful populations will obtain the bulk of their calories from plant based sources, that's irrefutable. Yes, there will be times, be it celebratory such as a full moon, or a birthday where this changes, or in cases of food scarcity - but for the vast majority of the planet, and the majority of the time, they survive on a predominant diet of starches, be it potatoes, rice, millet, barley etc... and then throw in all the fruits, veggies and so on.
The issue and why there's even a thread about dairy is the over consumption of the food - so while the populations you mention may need to consume dairy products for survival, here in the UK we're doing it habitually 2-3-4-5 times a day and that's where the problems start...