>>53540987Many things
1) Pokémonia was already on the decline by the time Gen 2 came out in the west
2) TPC didn't now how to handle new generations, they were still heavily focused on the Gen 1 Pokemon with Gen 2 pokemon treated more like rare finds than anything else. Even most merch was still Gen 1 Pokemon. Nothing on earth could compete with the original ONE HUNDRED AND FIFTY. The Gen 2 pokemon were just stuck being the "plus more to see".
3)The few Gen 2 pokemon that did got shilling were mostly the babymons that most fans hated
4) The anime was was on a sharp decline in viewership, partly due fans being pissed about CHARIZARD ruining Ash's chance at the league but even without that, fans thought that the anime was too "filler-heavy".
5) (Tinfoil hat time). Due to GSC being a sequel region, Game Freak/TPC don't respect the Gen2 roster and just sees them as KANTOOOO Filler hense you get bullshit like the Gen2 starers being skipped over whenever there's a cool new gimmick while Kanto and Hoeen get everything.
tdltr, The Gen 2 roster was sabotaged by a combination of bad timing, lack of marketing, and possibly spite.