But the scrollbars and widgets are not even similar, neither are the fonts, the color pickers or anything worth talking about... The only similarity seems to be blue-grayish tones, and possibly gradients (although the jpgs of the Samsung IDE are too blurry to really tell).

Surely you're not talking about the drag and drop grid either, which was around years before Apple even made IDEs.

There are plenty of lazy carbon-copied Mac themes for Windows and whatnot, this isn't even close, it's just yet another IDE with color tones that are vaguely similar to XCode (maybe ? how many windows apps aren't gray/blue these days ?).