So the block allowance (soon to be renamed to World Capacity) is there to ensure the game runs as smoothly as possible. Removing it, or even increasing it slightly, will have an impact on performance. It's important to note that Microsoft, Sony and Nintendo won't let a game be released on their platform unless it meets their strict criteria. So in essence, even for us to release the game on these consoles the World Capacity is essential.
PC platforms (Steam) have looser restrictions on performance as each PC is different. As long as the Minimum Specs for each game are made clear the player will have an idea if their PC can run the game.
I think the console requirements are more stringent about user shared content (policing it against things inappropriate for younger players, etc, etc). Presumably technically demanding to implement too, given the current system is integrated with Steam.
Not certain what you're asking... But the higher capacity cost of blocks is supposed to reflect the amount they tax the console's hardware. Like an SCU with all its complex shape, animations and effects takes a lot more than a plain GSO 1-Block.