While this may be slightly true, it's quite nice to have the knowledge you can still in some ways play your favorite games in blockland.
An upside to this is the ease in mapmaking, would you rather spend 10 days making that map, perfecting optimization, adding events, etc, or would you rather spend two days placing the bricks and spawn points and those other premade tf2 items? Sure, it may not be as fun as the real thing, but it's the second best thing.