Dark Souls, Disco Elysium and Stardew valley.
Stardew Valley. I never really cared for farm sims. I played the first Harvest moon on the SNES way back in the day but the other games never really caught my interest nd neither did a lot of other games of the type. However, Stardew Valley really clicked for me and I dumped a fair number of hours into it before getting to a point I was happy to let it go(I built up my house, got married, was making plenty of money, etc). I think much of it was not only the feeling of continual improvement to the farm but also the depth of the various characters in the town which could only be found by getting them to like you.
Disco Elysium. I more or less ignored this game when it was coming out, partially because the title made it sound like a disco themed music/rhythm game and partially because it wasn't by anyone I'd heard of(it also seemed to pop out of nowhere as well). Then it starts getting all this good press and I decided....why not? It was one of the most fascinating and satisfying experiences I've had in a long time. Not only by the whole stick of making the mundane interesting(most of the side quests are stupid little things that somehow work because of the writing) but also the fact your skills are continually talking to you and have more influence on you as you level them up.
Also, KIm is one of the best NPC companions ever. The fact the man clearly recognizes what a fucking nut the PC is and yet puts up with it anyway goes a long way towards making almost like a buddy cop in an RPG.
Dark Souls. So, I'm sure I've said it before, I am not one who cares for EXTREME CHALLENGE. I rarely bother going for achievements that require insane feats, I almost always stick to normal difficulty and I'm more then happy to find something that works and exploit it as long as it doesn't remove all challenge from the game. I played SNES/NES games way back in the day but don't miss how fucking punishing they could be. So the fact Dark Souls(and Souls/Souls-like games) embrace the "Prepare to Die" motto was not a selling point for me. It wasn't until I started hearing about the level design and the lore and to some extent how the combat was satisfying that I decided to give it a try, and while it took me a little bit to get into it, it eventually did. Now I've beaten Dark Souls, Dark Souls 2, Bloodborne, Sekiro and dabbled in Demons Souls, so yeah, I've definitely found the appeal in it.
Oh, and also Undertale, for reasons many other people have articulated. I also enjoyed Deltarune for being a really interesting take on a sequel.