It depends on what you consider oppressive. In terms of international freedom indices, South Korea is about as free as the United States of America (https://freedomhouse.org/countries/freedom-world/scores or https://rsf.org/en/index) or not far from it (https://worldpopulationreview.com/country-rankings/freedom-i...)

Of course this doesn't say much if you don't consider the USA to be a very free country but I'd reckon most of the world still does.