A popular cultural trend that leaves a negative impact on society, either through encouragement for the populace to ignore greater issues, even regarding itself, to direct more attention to
instant gratification (in more modern terms, "consume product and then get excited for next product"), mass psychological harm, glorification of
disreputable traits such as crime,
vulgarity, or materialism, or other effects that can leave a moral of intellectual "hole" in societal values.
K-pop is a commonly cited example of a
cultural sinkhole, with it's propagation of unrealistic beauty standards, immoral corporate practices, and rampant
idolatry of people based on personality instead of talent, all upon
impressionable youth, it's main demographic.