Desktop games and mobile games are not the same. On mobile pretty much every heavy game uses either UE or Unity. High end PC games use custom engines that are heavily tuned for x86 and use different APIs. Metal port would be expensive and not worth it.
Most games use licensed engines, most AAA games use their own engines. Only 3 out of top 10 games in Steam use engine that support metal. More than a half of games in top 100 use engines that don't support metal. In this month we have few prominent releases on PC: Guardians of the Galaxy, Far Cry 6, Age of Emires 4, FIFA 22, The Dark Pictures Anthology: House of Ashes and Back 4 Blood. Out of these 6 titles only last 2 use UE4, others use their own custom engines. And I could go on and on.
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