Yes, people with very mild astigmatism can still experience 20/20 uncorrected vision (vision without corrective lenses). However, the letters on the “20/20” line of the eye chart won’t be as distinct as they are for someone with no refractive error.
It is also possible for people with noticeable astigmatism to achieve 20/20 vision with glasses, contact lenses and/or laser vision surgery. However, it will depend on the severity and type of astigmatism.
If the degree of astigmatism is high, corrective lenses might not be able to provide 20/20 vision. Also, some types of astigmatism may not be corrected with lenses but can be corrected with refractive surgery.