People just don't want to have children and are no longer expected to by society.

You're looking for other early ethnographers, explorers, or accounts from the Arctic that corroborated Stefansson's observations regarding the Indigenous peoples' (primarily Inuit/Eskimo) lack of desire for salt. Multiple individuals reported similar findings, which strengthened the argument that salt craving was not universal.

Here are a few prominent figures and accounts:

Frederick Schwatka (1880s): An American explorer who led several expeditions into the Arctic (including a search for the Franklin Expedition remains). Schwatka lived among the Inuit for extended periods and adopted many of their survival techniques. He observed their diet and noted their indifference to salt, similar to Stefansson's later accounts.

Franz Boas (late 19th - early 20th century): Often considered the "Father of American Anthropology," Boas conducted extensive ethnographic work among the Baffinland (Central) Inuit. While his primary focus was broader cultural anthropology, his detailed accounts of their daily life, including diet, implicitly supported the idea of a salt-free traditional diet and a lack of specific craving for it. His work provided comprehensive documentation of their indigenous practices before significant Western influence.

Knud Rasmussen (early 20th century): A Greenlandic-Danish polar explorer and anthropologist, Rasmussen conducted numerous expeditions and spent years living with various Inuit groups across the Arctic (Greenland, Arctic Canada). His ethnographic works, such as "Across Arctic America" (1927), contain detailed descriptions of Inuit diet and customs. He frequently recounted instances where Inuit found Western foods (including those heavily salted) unpalatable or rejected salt when offered, reinforcing the idea that their palates were not adapted to it.

Diamond Jenness (early 20th century): A Canadian anthropologist who spent significant time with the Copper Inuit (western Arctic Canada) as part of the Canadian Arctic Expedition (1913-1918). His meticulous studies of their culture and subsistence included observations on their dietary practices, which naturally indicated a diet without external salt supplementation and no apparent desire for it.

Adolphus W. Greely (1881-1884): While primarily known for his ill-fated Arctic expedition, Greely's journals and subsequent writings briefly touched upon the diet of the local Inuit he encountered. He also described their simple, meat-based diet and the lack of salt in their provisions, often remarking on how well they seemed to thrive without it.