Pixelated graphics hit the right spot for me. The Binding of Isaac Rebirth, Stardew Valley, Enter the Gungeon, Dwarf Fortress, Dead Cells, Terraria, FTL, some emulated games. I got pretty addicted to Vampire Survivors at one point too.

Stardew Valley and Undertale. I also loved Duelyst, but it’s no longer around.

I used to have no interest in pixel-style games but in the past few years I’ve grown to really like them. I’ll try and post some of my favorites below with a quick synopsis to see if it’s something you may like. These are really in no particular order. As you can see, I really like the building/colony management games. I hope to delve into other genres at some point when they interest me.

Also, a lot will be in early access but I’ll note when there hasn’t been updates for a while.

Building/colony simulation

• Cult of the Lamb - you play an endearing and cute lamb that needs to start a cult in order to gain favor and allow your colony to thrive. You do this by going through rogue-lite dungeon levels and defeating enemies/bosses to recruit more followers and continue the story campaign. Includes some mini-games like fishing and a card game and I’m sure more. They just released a big update that I have yet to check out.
• Dwarf Fortress - One of the most complex colony simulators to date. You take the good with the bad. The UI has seen improvements in their recent Steam release but it’s still, at least in my opinion, not the most intuitive thing. If you are into this genre of game, though, you absolutely need to check this out and put in the time to learn the systems. You start the game by having it simulate your world’s history given some seed data. After it’s done, you can view every single action taken to see how the world got to this point (even seemingly useless stuff like Goblin Terry bought a tavern in Randomtown or whatever). Don’t sleep on it!
• RimWorld - heavily inspired by Dwarf Fortress, it’s basically that but in a sci-fi setting instead of a medieval one. While the interface by default is, in my opinion, better than Dwarf Fortress’s, it still requires quite a time-sink to get accustomed to. There are an incredible amount of mods on the Steam workshop that makes the variability and replayability seemingly endless.
• Clanfolk - RimWorld style game based in old Irish lore. Still in early stages but their testing branch is very frequently updated.
• Stardeus - Think RimWorld except you’re an AI on a broken down ship with a bunch of travelers in stasis. You need to repair the ship, get the systems working again, and improve everything over time. The developer is insanely active, with seemingly daily updates. For a while they were streaming all of their development on Twitch. I don’t know if they’re still doing it, but, it doesn’t matter; he’s still updating the game at a ridiculous rate. It has full modding support as well but there are far less of them at the moment since the game is in early access and much newer.
• Songs of Syx - Alright, this game is kind of nuts. Instead of managing one colony like in Dwarf Fortress and RimWorld, your goal is to manage a large part of the rendered world. It has a lot of the same building elements as the other games but takes it to another level. Also, it’s medieval style and has magic. You really should not sleep on this if this sounds interesting. Obligatory warning: yes, it has a massive learning curve and things aren’t well documented. There are some good guides on YouTube, though.
• Oxygen Not Included - Similar to RimWorld systems and mechanics wise with a completely different look and feel. It’s too complicated for me right now to look into much but I need to mention it as it’s insanely popular.
• Core Keeper - A completely different game this time. In this, you actually control a single character in top-down view. There are multiple different biomes that you move on from by defeating bosses. It’s like Stardew Valley with much more focus on combat and it takes place underground.
• Keplerth - I’ll be honest, I couldn’t get into it, but, I’ve seen posts here and there about people loving it so I thought I’d just include it in the list.
• Necesse - Again, haven’t played it much, but, if you know about the game Terraria it seemingly tries to improve on those systems.
• Realms of Magic - In the same vein as the previous two, but, my favored one. It has basic story elements, complex building and crafting, and a pretty cool map system. If the Terraria-style game looks nice to you but you want more, check this out.
• PixARK - Officially licensed pixel style ARK: Survival Evolved clone. It feels a lot easier and I enjoy it more. The issue I have with it is that updates got really slow for a while. They seemed to have picked up again recently so maybe it was just a temporary thing, not sure. Quickly looking at the patch notes, though, there doesn’t seem to be many significant updates lately (if at all).

Metroidvania style

• Infernax - From the Steam page: Infernax is the adventures of a great knight who returns to his homeland only to find it plagued with unholy magic. Uncover the mysteries of the curse and face the consequences of your actions.
• Blasphemous - A super dark art style and challenging combat. You play some fucked up angel type thing that’s basically on a good-guy crusade. Fight evil, etc. I can’t do this justice though, it’s legitimately very impressive. A sequel was recently announced.

Dungeon-crawling ARPG

• Chronicon - A bunch of really cool classes and tight combat systems makes this one a favorite.
• The Slormancer - Really awesome (and intuitive) builds with a great art style. You can upgrade pretty much any of the systems in the game (think magic types, health, etc), making it really easy and fun to try out different builds.

Carrion. I’ve never played a pixel art reverse stealth game where the player is the horrible monster. and I bet you haven’t either!

I’m not sure if it is truly considered a pixel art game, but I still love Terraria.

Dead cells never gets old

Gotta be hotline Miami. I described it to my brother as John wick/the punisher with original grand theft auto graphics.

I really liked CrossCode. It’s is a Zelda-like with solid gameplay and a fun story

FTL is great, into the breach as well.

Heros Hour is also cool

Celeste and Shovel Knight are my favorite semi-recent games. I’m always game for A Link to the Past though.

Noita is kind of niche but it’s really a fun time. Easy to pick up and put down.

Do you want pixel graphics, or do you want gameplay like Vampire Survivors? Because the suggestions here are all over the place genre-wise.

Don’t think this is exactly what you’re asking, but among actual old games, A Link to the Past and Super Metroid are both highly playable and highly replayable pixel graphics games.

Stardew Valley. So relaxing to play and the progress feels rewarding too. You can also play with someone else co-op which makes it more fun.

A Short Hike, it even has settings to make it EXTRA cruncy (big pixels) or to smooth them down.

Edit: forgot to mention the “why”: it feels like a true labor of love, which is a rare sensation for me to experience.