Raw milk is not commercially viable, really that's what it comes down to.

Commercial dairy farms use pasteurisation for 2 main reasons.

Increased shelf life(if you leave raw milk for a few days(and obviously keep it clean) it will turn into yogurt, because the living enzymes and whatever lactic acid bacteria and stuff that's naturally in the milk)

And lower hygiene standards required(the pasteurised milk can contain traces of shit, blood, puss, and who knows what else but because it's been pasteurised all the bacteria is dead and you won't get sick.

If you don't wash the cow properly before milking, or if anything other than milk ends up in the bucket raw milk becomes unsafe to drink.

If you want to drink raw milk sheep and goats milk is much safer.

Cows natural skin microbiome has Ecoli and botulism bacteria and a whole bunch of other stuff that is harmful to humans.