Deep Silver and Epic have recently announced that Metro Exodus will be skipping its launch on Steam in favor of Epic Games Store where it will be an exclusive. It appears that this might have been a surprise move because Valve had previously put up a pre-order page for Metro Exodus on Steam, but they have since discontinued it. However they did state that those who had previously placed their pre-orders for the game and its DLCs will have their purchases honored.
According to Valve, “We think the decision to remove the game is unfair to Steam customers, especially after a long pre-sale period. We apologize to Steam customers that were expecting it to be available for sale through the February 15th release date, but we were only recently informed of the decision and given limited time to let everyone know.”
Note that apparently this exclusive is not permanent. Deep Silver has since clarified tat Metro Exodus will return to other storefronts after the 14th of February, 2020. This is not the first game that Steam has “lost” to Epic in recent times. Previously Ubisoft also announced that The Division 2 will be launched via the Epic Games Store.