Additional Islands in random map generation

Given the other things going on with Age1DE, this is probably more of a minor problem.

I remember playing Age 1 on Island maps a lot, so I wanted to recreate the experience in DE. But that seems not be possible, because the random map generation seems to be different in one key aspect: there are no additional islands generated, only the player ones.
I installed Age1 (with User Patch) again and tried it there, and it generates addtional islands with resources.
Since Age1DE doesn’t support custom map scripts, I have no way to change this myself. But I’m mostly curious why this was changed. Really takes something away from my personal experience.