Your point about reducing pointer size if the size of allocation pool is smaller makes sense. But I think it is not fair or realistic to imply that simply using

Your point about reducing pointer size if the size of allocation pool is smaller makes sense. But I think it is not fair or realistic to imply that simply using an array the size of all RAM starting at zero leads to more fragmentation than referencing all of RAM relative to some other point. Assuming same algorithms working on same sized data sets. The relative locations of objects is not dependent on where the coordinate origin is, although choosing a good zero may make the engineer's life easier.