> You don't have to be taught to breathe.

You sure? Haven't read the book / heard of the author. But after I started freediving and training holding my breath (also called static / dynamic apnea lol) and working a lot on related stuff, I realized I was mostly breathing shallow and with my chest, and not deep with my abdomen.

Now I notice it in others. I don't know if it matters in the end. But I breathe a couple of times a minute and then I hear people next to me quickly breathing in and out constantly like a rabbit. Seems stressful?