Everyone has certain tropes and backgrounds in games that appeal to their tastes. It could be as simple as a genre or the difference between linear and persistence versus effervescent, procedural generation but theres always something you hear about a game that make you give something a second glance and go 'oh hold on a minute, whats this?' and gets you invested.
For me i think i'm a sucker for the setting that uses the "once marvel of the world city turned to ruin" idea. Places like Rapture in Bioshock, Lordron and Drangleik in Dark souls, Hallownest in Hollow Knight and even in objectively shitty games like the floating arcology that was lost at sea from Brink. Its games where you are largely a solitary character, often with little reason for being there beyond stumbling upon the location at all, who delves into some long, long epilogue to a massive disastrous event to explore and maybe figure out what happened here. Often with a similar progression of 'normal looking abandoned areas with feral, murderous people as enemies' to a journey to the root of it where things become more monstrous and nightmarish in both location aesthetic and enemy variety.
Theres plenty of other genres and tropes i like but the whole 'what happened here? will i piece it together over time or will this just be a lonely adventure for adventures sake and it will all remain a mystery with a bitter sense of melancholy that this world was once something grand?' vibe you get from these kinds of games. Its kind of ironic since i usually roll my eyes at people that play games for "the lore" rather than immediate stories as the worst kind of 'watercooler videogames' but i find this setting is the only one that gets the balance between environmental storytelling and active, ongoing developments right to a degree of success i dont find in cases of things that are outright post apocalyptic world settings. Maybe it just stems from a personal love and fascination of really well composed, high quality photography of real world places that have been abandoned and retaken by nature combined with the old go to trope in stories when i was a kid of 'tumbling down the rabbit hole' where often these places aren't set in a ruined world, they are an isolated freak occurrence, but maybe its up to you to ensure it stays that way and never spreads.
But thats just me, i know plenty of folks who find that mind numbingly dull and would rather see a game set during the events than long after in this kind of setting, but what about you? what trope or setting for a game is a super easy sell for you?