lol the thing is, it's not just us foreigners who complain about how awful koreans are at enunciation. ever noticed how every single video in korean has subtitles? they can't even understand each other kek (but it's good bc people who have trouble hearing can watch most content w/o any problems). even most k-drama actors have to work with a tutor in order to make their pronunciation as clear as possible.
also, nowadays young koreans tend to speak v nasally. not only does it sound annoying af but just makes it harder to understand them.