The Bering Strait theory is NOT losing traction. The more the DNA is tested, the more solid it gets.
Native Americans are most closely related to people now living in Siberia.
Have you had your own DNA tested yet?
My mother's descended from Chippewa women, and her mitochondrial DNA is very similar to Aleut DNA and Siberian DNA.
https://www3.nationalgeographic.com/genographic/atlas.html
I would love to get my DNA tested for sure.