In this vein, and in the context of early twentieth-century progressive party-crashers and a national campaign of widespread displacement and re-education, it’s no surprise that the activist and academic communities felt entitled to an opinion about the rearing of Native American children.
A quick literature search reveals a wealth of efforts from anthropologists and social reformers to make sense of, justify, critique, or otherwise worry their pretty heads with the issue of cradle boards and their effects on Native American children.
For instance, a 1966 article in the American Anthropologist discusses the presumably counter-intuitive idea that cradle boards are just fine for Native American children — but insists that this is so for scientific, rather than magical, reasons.
The foregoing discussion provides an example of an exotic custom which is magical in its rationale, but which nevertheless succeeds in doing what it is intended to do. It is therefore comparable to ‘Voodoo’ death, divination, and other magical techniques that ‘actually work’ 
A long and boring discussion of isometrics and infant strength precedes this statement. And thank goodness, because this little girl below totally needs the anthropologist’s approval.
These explorations of Indian mothering weren’t idle academic curiosity — they resulted in policy decisions that deeply affected families. Many white women missionaries and reformers believed that transforming Indian girls’ methods of raising children and keeping house were central to the assimilation and civilization of Indian people, and they lobbied for new government policies to remove Indian children from what they perceived as their pathological home environments. For example, Estelle Reel, the Superintendent of Indian Education from 1898 to 1910, declared that
The homes of the camp Indians are to be reached mostly through our school girls, who are to be the future wives and mothers of the race, and on their advancement will depend largely the future condition of the Indian. All history has proven that as the mother is, so is the home, and that a race will not rise above the home standard. 
In practice, this meant that Indian children were to be taken from their homes and communities and institutionalized in distant boarding schools where they would be re-educated and re-socialized.
The writings of the Women’s National Indian Association — a progressive-era organization formed with the mission of protecting Native Americans from encroachment of white settlers — exclaimed the need to “get the babies off the board,” and explained that missionaries “would do a good work if we accomplished only [the cradle board’s] abolition.” The author hoped to teach each American Indian women “to hold her baby in her arms, and to put him upon a bed to sleep, ‘as white squaws do.’” 
The interest in cradleboards and their effects on infants endures. A recent article in the American Journal of Physical Anthropology reports that
this study suggests that the pressure and friction of an infant’s head against a cradleboard may have 1) produced ischemic ulcers, 2) produced the conditions favorable for bacterial infections such as impetigo or carbuncles, or 3) complicated the treatment of other infections appearing on the back of the scalp. 
But, as every parent from every generation knows, we’re all doing stuff to our kids, some of it recommended by the “experts”, that will probably make them crazy and hate us, or be decried as lethal or harmful by future “experts”.
 Hudson, Charles. 1966. Isometric Advantages of the Cradle Board: A Hypothesis. American Anthropologist 68, no. 2. New Series (April): 470-474. doi:10.2307/669347.
 Margaret Jacobs, “Playing with Dolls,” The Journal of the History of Childhood and Youth 1, no. 3 (2008): 321-328.
 Diane Young Holliday, “Occipital lesions: A possible cost of cradleboards,” American Journal of Physical Anthropology 90, no. 3 (1993): 283-290, doi:10.1002/ajpa.1330900303.