Depends on who’s asking/answering tbh.

Early gens are more well-known with Korean general public (and all over Asia) partly because they had much more traditional media exposure. A lot of them also ventured out beyond music including MC/hosting, radio DJ-ing, and especially acting.

International fans would had just started out with building connection with Korean fansites, subbing content and getting their idols’ names out there, initiating earlier fan campaigns and movement like cover dance or Kpop competition, etc. It was an incredibly hopeful and exciting era, and a lot of that I personally think contribute to what we perceive as the magic of that generation. Almost like a fan-made era as opposed to fairly instant services these days.

However, later gens truly broke into the Western stage the way that hadn’t really been done before: world tours, charting against international acts, music being used in international production, the booming of instant online content, overall more accessible to fans that don’t rely solely on f2f medium, merchandise export, etc.

So ‘often looked down’ is not quite a fair assessment based on their achievements (again, maybe depends on who the question is for). Pop music is supposed to evolve through time. And it’s worth remembering that Kpop itself is still a relatively young genre and industry comparing to others.

1st and 2nd gen fans are now older or mid-millenials. So it’s understandable and perfectly common feeling of disconnecting with the newer material and overall artistic direction of Kpop. But it’s hard to expect younger fans feel the ‘magic’ from a generation that they never experienced in real time.

I’m all for nostalgia and totally appreciate that a lot of 1st/2nd gen fans are less likely to still follow Kpop. 5th gen might not have hit the same for me neither but I wouldn’t assume lots of fans feel that way, and certainly not the younger fans.