This article at the end mentions a famous Halachic distinction made between the prohibition of 'Ever Min HaḤai as it pertains to Jews vs gentiles. For gentiles 'Ever Min HaḤai doesn't apply to milk, because it isn't connected to the animal. For Jews, however, there is an added stringency that includes even the milk, which is why the Jews needed special dispensation in the form of the verse that praises Eretz Yisrael as the "Land of Milk and Honey". For this reason, according to the article, Bnei Yisrael never ate dairy prior to Matan Torah, which we commemorate by eating dairy on Shavu'oth. But isn't this internally contradictory? Bnei Yisrael had the same level of 'Ever Min HaḤai prohibition as gentiles prior to Matan Torah!
I checked the source mentioned in the article cited:
You can read it yourself here.
Rabbi Shlomo Kluger says that non-Jews could drink milk, since milk is not a limb. One of his proofs is וַיִּקַּח חֶמְאָה וְחָלָב - and Avrohom fed them butter and milk!
I do not see any mention of the articles conclusion
From what I can see, he does mention that
The question now becomes, where/how did Rabbi Shraga Simmons get his Chidush of
Added on 4 Sivan 5773:
I received the following response from Rabbi Shraga Simmons:
I have not had time to study the response, but I do want to record it.