At the end of the day gachas live or die on character design alone, unfortunately no hsr character(s) have genuinely good design and writing that makes them stand out,
Meanwhile pic rel
Makes a tenth of hsr's gacha revenue monthly(no content in the game that forces players to pull for gigameta chars)
But has other gachas beat in terms of fan content and side content
Instead of pumping new characters every 2 months they instead release alts of already existing characters to expand on them more
Further expand character interaction through youtube shorts
Shits out so much merch they spend 3hrs talking about it in the anni stream
Pic rel is the complete opposite of how mihoyo handles their gacha and i guess its working out for them they have been relevant now more than ever and thats with a targeted niche fanbase