You can't talk about this without starting with Gillian Flynn, can you? 'Gone Girl' basically rewired the whole genre for a decade, and her other books are just as sharp. She's got this unmatched talent for making you deeply unsettled by the people you're reading about, and you end up questioning your own judgments.
Alex Michaelides is another one that comes to mind, though I find his stuff a bit more polished and maybe a little less raw. 'The Silent Patient' played with unreliability in a way that felt fresh at the time. For a slower, more atmospheric dread, I keep going back to Tana French. Her Dublin Murder Squad books, like 'In the Woods', aren't pure thrillers in a chase-scene sense; the suspense is all about the psychological weight on the detectives themselves. That lingering, unresolved tension gets under your skin differently.
I also think Ruth Ware deserves a nod, even if her pacing is more methodical. She builds that claustrophobic, 'can't trust anyone' feeling really well, especially in 'The Woman in Cabin 10'. So yeah, those four would be my core list.