I almost never play computer games, but what I sometimes like are classic logic games like Minesweeper or Sudoku. And I must say, the versions from GNOME (on Linux), GNOME Mines and GNOME Sudoku are really nice. Simple design, plain and focused on the game with the most important features. I have also just discovered on the GNOME Wiki that there are a number of other simple games available, like 2048, Four in a row or Chess (Chess is probably not so simple). I install most apps via Flatpak and Flathub, but most distributions should also have them directly in their repositories. The advantages of Flatpak are that it is very easy to install and you always get the latest version.