Twilight struggle is freaking amazing. Only thing is it takes some time to learn, is a bit long to play, and there's a meta you start to learn/develop as you play. It's amazing because there's several win conditions, so both players are trying to balance out those win conditions, often even intentionally giving up an advantage for potential future advantages. Highly recommended.

While I used to always target longer more in-depth sessions of Memoir44, Kontor, 7 Wonders Duels, Starship Catan or the like, in recent years I would say the most 'fun' I actually had with less involved byte-sized 2 player options.

My favorites in recent memory are things such as:

• Onitama for an instant chess 'end-game' struggle with weird bendy movement rules that are different each time (and can be between nail-bitingly close or hilariously unbalanced)
• Lost Cities for an old classic which can be played leisurely in the background over a nice drink while still generating enough excitement in the game itself
• Quorridor and Abalone for abstract little time fillers that you can always fit a round in and generally don't demand too much of you
• and my recent favorite Air Land Sea for a short but intense struggle along three lanes, deploying simple open scoring cards while trying to lay devious traps without the other player noticing. Some of the best balance of hidden and open information I've come across for 2players.

I think I have moved from the game constantly being the center piece of attention to games focused on more punctual 'attention' points for 2 player games, which allows a nice conversation to flow around but still leaves you with something to do in between. I guess shorter games are a more natural fit for that.

Duel for Middle Earth is a great time. Wife and I have played dozens of times and it's always a nail biter.

Shogi, hours of fun conversation playing with different levels of difficulty

Fox in the forest is a quite simple but super fun game

Mage Knight, if I have half a day to kill. War chest, if I'm feeling thinky. Jaipur is good for casual fun and it's luck based enough that beginners have a chance to win.