Why does creating an array using the spread operator returns something, while not using the spread operator the other doesn't?

Question

If I type in the browser console Array(100).map((x,i)=> i) it returns an empty array as follows:[empty x 100] But if I use the spread operator [...Array(100)].map((x,i)=> i) it returns all the indexes [0,1,2,3,4,...].

If I am not wrong, using the spread operator creates a shallow copy of the newly created array, but I don't understand why the map works on the second version and not also on the first.