If someone has thick yellow, brown fungal finger and toe nails and then amazingly this disappears a year later with no treatment, why would this be?

luck?

I don't think u get rid of fungus without some kind of treatment

Either it wasn't nail fungus but something else that looked like it or you improved your immune system through changes to diet or maybe you were inadvertently using something that was naturally antifungal?

could be you washed your feet.

The fungus has abandoned ship or something much worse has killed it..😷