Boundaries Are Culturally Built, Not Innate
Western culture teaches you to maintain boundaries: self/other, inside/outside, control/chaos. These aren't necessarily natural categories. They are largely cultural. All of these train you to experience yourself as a separate, bounded entity that must manage its interactions with an external world. If something upsets you, the problem is often framed as your boundaries being too weak or too porous. But before that training, a baby doesn't experience themselves as separate from their caregiver, from sound, from sensation. I'm skeptical of the boundary story. Or, let's just say I'm ready for us to find a different frequency.