Right. The theory in Eberron is that all intelligent beings are capable of making moral choices and can decide their own alignments. While you might see cultural biases towards alignments in some cases, free will ultimately wins out. Thus your average goblin is more or less as likely to be good (or evil) as your average human.
Dragons are no exception and are assumed to be born without a predisposition towards any particular alignment.
There are only three major exceptions.
1. Outsiders are assumed to be manifestiations of cosmic principles and so are overwhelmingly pushed towards a specific alignment by their very nature. (But even then, nothing is absolute.)
2. Undead are inherently inclined towards evil, though free willed undead can still reject this evil more easily than outsiders.
3. Lycanthropy is a mystical curse that can change your alignment by altering your very soul, which is the reason it's so feared.
Dragons are no exception and are assumed to be born without a predisposition towards any particular alignment.
There are only three major exceptions.
1. Outsiders are assumed to be manifestiations of cosmic principles and so are overwhelmingly pushed towards a specific alignment by their very nature. (But even then, nothing is absolute.)
2. Undead are inherently inclined towards evil, though free willed undead can still reject this evil more easily than outsiders.
3. Lycanthropy is a mystical curse that can change your alignment by altering your very soul, which is the reason it's so feared.