Were the Yamnaya people lactose tolerant or lactose intolerant?

Are rh negatives more likely to be lactose tolerant?

This just came to my attention:

We now know from archeogenetics that the Yamnaya people were lactose intolerant, as were all the steppe peoples. Those among them who did have domesticated animals (not all did) would most probably have been eating cheese, like the Neolithic farmers, not drinking milk, or they would have been incapacitated. As for milking horses we now have the recent paper about the introduction of sheep and goats onto the steppe, and it specifically says milking horses only started during the Iron Age.

https://www.eupedia.com/forum/threads/42454-early-european-farmers-suffered-from-malnutrition?p=645534#post645534

Rh Negative Origins: The Yamnaya People

I always thought the opposite.

Here are some additional thoughts from others:

Kennett, who helped establish the chronology of milk consumption by directly radiocarbon dating individuals from the EBA, noted that Yamnaya were likely lactose intolerant since the gene for processing lactose in adults didn’t become common until the Iron Age (beginning ca. 1200 BCE) in Europe.
“This would suggest that they were fermenting the milk or making cheese,” he said. “Also, kids have lactase persistence for several years after they are weaned so it could have been important for childhood survival as a weaning supplement.”

https://www.news.ucsb.edu/2021/020403/milk-revolution#:~:text=Kennett%2C%20who%20helped%20establish%20the,1200%20BCE)%20in%20Europe.

But then there is this:

Furthermore, ancient DNA studies found that the LP mutation was absent or very rare in Europe until the end of the Bronze Age [26–29] and appeared first in individuals with steppe ancestry [19,20]. Thus, it was proposed that the mutation originated in Yamnaya-associated populations and arrived later in Europe by migration of these steppe herders.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7302802/

So it is quite possible that Yamnaya became lactose tolerant over time.

Lactose persistence being a more recent mutation was also discussed here:

The Bronze Age of Eurasia (around 3000-1000 BC) was a period of major cultural changes. However, there is debate about whether these changes resulted from the circulation of ideas or from human migrations, potentially also facilitating the spread of languages and certain phenotypic traits. We investigated this by using new, improved methods to sequence low-coverage genomes from 101 ancient humans from across Eurasia. We show that the Bronze Age was a highly dynamic period involving large-scale population migrations and replacements, responsible for shaping major parts of present-day demographic structure in both Europe and Asia. Our findings are consistent with the hypothesized spread of Indo-European languages during the Early Bronze Age. We also demonstrate that light skin pigmentation in Europeans was already present at high frequency in the Bronze Age, but not lactose tolerance, indicating a more recent onset of positive selection on lactose tolerance than previously thought.

https://pubmed.ncbi.nlm.nih.gov/26062507/