I think the homogenisation plays a big role though. From supermarket milk I get mucus and digestive issues. Not from raw milk. Kefir made from supermarket milk I can tolerate.
I used to get milk for a little while from a farm that pasteurized but used no additives, no supplements, did not homogenize and packed in glass with plastic cap. I kind of "energy test" with my hands. It tested much better than Horizon brand organic homogenized pasteurized milk in cartons every time I tested. I had no milk allergy, so I don't know what else I can say.
I never made kefir with pasteurized milk, but I made yogurt with pasteurized. The unhomogenized always made better flavored yogurt. Unhomogenized yogurt always made better starter than using artificially homogenized yogurt to introduce culture it.
I don't mind grainfed raw milk, but I know grassfed raw is better. The son I've talked about before dislikes the taste of raw grainfed, and likes the taste of raw grassfed. He did have extreme dairy allergy (not sensitivity nor intolerance) to pasteurized, but not so much with unhomogenized. The problem was with plain yogurt, cheese, chocolate ice cream (perhaps other flavors but we didn't try) and Lactaid lactose reduced milk too, even food with only a tiny bit of whey in them. Heck, he's so sensitive, he'll feel it if you take a sip of pasteurized milk in the next room. I've never seen grassfed pasteurized.
I tried grassfed pasteurized butter. It messed up my lymph big time, but I ate primal diet dose even though it wasn't raw. Heated grainfed (1 small serving) messed up my gall too, but not as bad as the lymph.