Thanks for the question. In general, people do outgrow their acne, but about 20% may have acne that persist in adulthood.
I do think that it is important to treat acne as it will improve an individual's appearance and self-confidence. Another important reason to treat acne is to prevent permanent scarring. Left untreated, acne can developed depressed and hypertrophic scars, which will persist.
There are now many good treatments that can control acne and prevent scarring so I do advice seeking treatment with your doctor/dermatologist to get the acne controlled.