In genshins case, that's an alright game aside from the gacha mechanics. People like it because of the cast of characters that can only be unlocked via gambling for them. Everyone has a favorite and sees cool fanart online and then wants to have them.
Love and deepspace on the other hand, is pretty much propped up on sex appeal. Women will spend embarrassing amounts of money for media that prioritises their desires over what men think they want. I should know, I am one (despite not having played love and deepspace because of the gacha mechanics, I do like otome games)
*gambling. It's been around centuries, nothing new
It's only rare cos they programmed the drop rate. Might as well sit rolling a dice and trying to guess the numbers.
Makes you wonder why they never added any rng into chess, ya know, to keep the player base "engaged"
arguably this is why Chess960 was created