Minecraft is a special case, as the amount of voxels in memory and the constant loading and deloading of blocks of the map every few seconds, means that memory management is incredibly important to the game. That's why the C++ version was more performant, as John Carmack had full control of both the memory layouts and lifetimes, and could fine tune it all to fit the game.

This is the only reason C++ is still in wide use today, in order for games to limit load times they have to do nasty 'unsafe' tricks (such as loading a block of memory from disk straight into an address space, and just assigning pointers to it), in order to get good performance. But if your game isn't open world (such as minecraft, GTA, Fallout), then using a garbage collected language will be fine (as long it's not stop the world, but runs concurrently).