Regarding Aetherborn Alignment:
That kind of language in D&D is always guideline, rather than iron-clad law. "As a rule" usually indicates a rule of thumb.
Aetherborn are
.
promotes its self interest ahead of other ends. This is one of the elements of "Evil" alignment in D&D, so
entities (Races, groups, individuals...) would tend to skew away from good. Remember, kids! In the Great Wheel, unlike in life, doing the right things for the wrong reasons is still the mark of the bad.
I made this chart once, depicting where I felt colors skewed versus alignment...
Attachment:
colorsandalignments.png [ 18.46 KiB | Viewed 3397 times ]
Regarding the Document as a whole: Since they didn't include it or even mention it, here's
A link to the Artificer class for D&D 5e that they published online earlier this year. Frankly I'm shocked it didn't even get a line in "Classes on Kaladesh".