Reasons for NewJeans' Popularity (By Generation):

Teens TikTok-worthy, easy-to-imitate fashion

20s Cutting-edge music and fashion, cohesive worldview

30s Nostalgic sound, refined visuals

40s and up Buzz factor, natural exposure through family/kids

Data Backing the Popularity
Spotify total streams: About 6.9 billion, monthly listeners 14 million

Guinness World Records: Fastest debut to 1 billion streams

Top charts in Japan.

YouTube MV views: Tens of millions to billions

Facts on Production Setup
Not just Korean creators—overseas talent from the US/Europe, etc., also involved.
Produced with an international perspective; can't be explained away as just domestic hype or number-fudging.