Most of the Americas does not have spicy cuisine. Domestication of chilis was a Mesoamerican & Andean thing and even today they haven't spread to all cuisines in the hemisphere.

My stomach has never been the issue with spicy food. The issue is when there's too much capsaicin, it is just agony in my mouth. It makes me fucking hiccup. And due to the physical properties of capsaicin if the food is too spicy every bite just makes it worse and the sensation takes forever to go away even while drinking milk.

I really do not get why anybody seeks it out outside of some perverse "dudes rock" self flagellating thrill seeking. Things taste better when you use peppers that have flavor other than "ow"

That might be COVID related if it's recent. One of the ways flavours changed for my sister after her second bout was spiciness becoming much spicier, to the point of pain at even a very small amount.