It just became way less of a hassle to launch 2K games from your Steam library. The publisher has officially removed its launcher from every game that used it on Steam (and the Epic Games Store). The removal went through on November 18, but a follow-up update to ensure the Launcher was fully removed dropped on November 25.
Many games, including Bioshock Remastered, Marvel’s Midnight Suns, and The Quarry, will now launch directly through Steam. Other games used the launcher for additional functionality. Those games will now launch a small submenu before opening the game itself.
For example, XCOM 2 and XCOM: Chimera Squad used the 2K launcher for mod management. Now, launching the game will open a small menu which will let you open the mod launcher or the selected game directly. For both games, this change lets you install and use mods on Steam Deck, though the Chimera Squad menu may have some graphical and interface glitches on the portable device.