Depends on the onion. A sweet onion, like a vidalia, is almost edible for me. We east green onions raw all the time, and red onions raw, in small amounts, on salads. It’s just volume that makes onions challenging. And age. Onions get more potent as they age.

But I’d eat a fresh, raw Vidalia; I wouldn’t enjoy it, but it wouldn’t exactly be suffering.