Complex sentence: His experimental surgeries without anesthesia on enslaved African-American women who could not consent are considered by many to be unethical, as well as symbolic of the historically violent oppression of blacks and vulnerable populations in the United States.
Split into simpler sentences: His experimental surgeries without anesthesia on enslaved African-American women who could not consent are considered by many to be unethical. This sheds a light on the historically violent oppression of blacks and vulnerable populations in the United States.