These are some games I've played that do not require reacting in real time.

Cosmic Star Heroine -- described as "remember your favorite 1993 JRPG? this plays like your fond memory, as opposed to how that game actually played". Ultra-polished gameplay, blunt, thin plot, no dialogue trees and no sob stories. OK, one sob story.

The Witness -- also known as "fuck yeah science, the puzzle game". Unleash your inner Feynman and make sense of the unspoken 'puzzle rules` by reasoning about examples.

Superliminal -- The inverse puzzle game to the above, where you can only get ahead by aggressively keeping your inner Feynman in check, and thinking laterally. Has similar snarky, meta vibes to Portal and Stanley parable.

Inscryption -- people say this is a "deckbuilder roguelike" so the immediate response is "oh you mean like Slay the Spire?" and the answer is no. While there is some deckbuilding and some roguelike-ing, this game stays away from the pure mechanical polish of those genres, and you could even say the entire game is a commentary of the sterility of pure mechanical polish in game design.

Wasteland 3 -- an irreverent turn-based RPG set in a post-apocalyptic future, and honestly a breath of fresh air in the landscape of generic high fantasy RPGs where you spend 30% of the game running an errand, taking the wrong turn, stumbling on a magic fire-breathing weasel 15 levels higher than you, getting wasted and loading your save.

9 People, 9 Hours, 9 Doors -- a classic of the visual novel genre. A bunch of strangers trying to survive a sadistic game -- so, inspired by Jigsaw, and in turn a part of the genre that ended up inspiring Squid Game, if that helps set your expectations. Has some of the infamous excesses of Japanese media but concludes in what is IMO a contender for the best twist ending of all time. For most platforms this game can be found bundled with its sequel, under the name "The Nonary Games".

Slay the Spire is a classic, it's all turn based, playing is easy but mastering it is a deep skill if that's something you're into.

Divinity: Original Sin 2 is a cool CRPG, the exploration is real-time and it switched to turn based for combat. Very big and large, and you can spend a lotta time running around learning lore rather than fighting if that's what you like.

Persona 5 Royal is a dream, again turn-based fighting, cute characters and story, very anime. Also long (took me like 90 hours) but never feels drawn-out.

If you like board games, I've recently got the Aeons End digital adaptation, and that's a lotta fun. It's co-op, but you can play "two-handed" (aka control 2 people) and it works pretty flawlessly, and the app is very good. If you really wanna be ambitious you can even play up to 4-handed, but I feel like that's too much brainpower for any sane person lol

Subnautica does have freedom and fun modes letting you ignore food and stuff like that. But I will say skipping the crafting, it loses something. The gradual increase in depth and pressure you can take is really satisfying.

I like turning off food and water needs though. That's just tedious

I find Townscaper really relaxing, there's no objective, just a toy to make cute looking towns. Haven't tested it on steam deck tho.

If you like building/puzzles there's Shapez (this one I tried on steam deck and it might take some time to get used to the controls), it's like factorio but abstract and without resource management, you just make machines that modify and combine shapes to create new ones, it get's progressively complicated, if it's your thing you'll find it quite addicting so be mindfull of that.

For sims there's Two Point Hospital, (Two Point Campus came out recently but I haven't tried it), Planet Coaster and Cities Skylines (if you're into the hard stuff)

Here are some more narrative driven games that I like:

• Life Is Strange: Graphic adventure with a cool twist and a compelling story
• Child of Light: Chill RPG in the style of a children's story
• Blacksad: Cool detective graphic adventure
• Both FAR games Lone Sails and Changing Tides: Puzzle platformer with a story told just with the environment, I recommend playing both one after the other in order
• SteamWorld Heist: Tactical RPG in a side 2D perspective with ricochet. I haven't played much of this one but it's very cool
• Gris: an interesting platformer with really nice looking animation
• A Short Hike: A cute adventure game about exploration
• Oxenfree: An interesting graphic adventure with a cool story
• Night In The Woods: Platformer adventure with an interesting story and great characters

The Outer Wilds. If you have a keyboard and mouse Cities: skylines.

The outer wilds is mostly pretty chill and relaxing and one of the best games I've ever played. Don't look up spoilers if you pick it. It's a game about exploring and curiosity

APICO maybe? It's got some crafting, but is mostly pretty chill, concentrating on breeding bees.

Dorfromantik is relatively mindless. You place tiles and create landscapes. There's nice music too. There's a sort of strategy to it, but it's pretty light. Unlocking new tiles is the main grind. If you wanted a bit more thought involved, just about any turn-based strategy like Civilization 6 should do.

If you want to keep to JRPGs but at a calmer pace than FF7R, False Skies might be up your alley. ARPGs like Chronicon are also low on the intense/concentration scale (although like most ARPGs, you shouldn't expect much of a story).

But more than any of those, I think Dave the Diver is your best bet. Ocean theme, doesn't require great concentration (besides the odd minigame), and has a bunch to be taken in at your own pace.