I heard you should not have dirt around the base of the fruit trees so they can breathe. so just leave about 1 foot from the base of the fruit trees bare (aka expose roots system)

is that correct?

All trees have a flared area or collar at the bottom of the trunk which should sit on top of the soil. It needs to be exposed but the root system does not.

Bare from weeds, yes. Digging out and exposing roots? I don't think so. The reason for bare ground around the trunk is to discourage rodents that eat the bark.