They were all doing variety shows constantly and making TV appearances to stay visible in the public eye. Even then only top Tier groups from 2 nd gen to a certain degree are still known and popular now.
Current groups don’t do variety shows or TV appearances majorly compared to previous gen idols. Nowadays the main focus is on building fandom, these groups have their own YouTube channel or Vlive channel to do videos and promote on their own terms while occasionally showing up on TV.
However top sellers of 3rd gen are well known in to the public. Most people would be able to name the top 3 if u asked them even if they didn’t listen to them
When I wrote that comment I didn't have in mind the top 3 groups
it was about top physical sellers like txt, stray kids, got7, nct, seventeen, monsta x, etc that sell very well but lack public recognition compared to older groups that never reached the "top 3" like infinite and block b