You are correct that such things are not normally categorized in such a way. However, you seem to be forgetting the Magic Rule where the card can override the normal rules of the game. Including isn't a problem, because the card takes precedence. Meaning that if it says they're included then they are included.
So, basically what's happening here is the card is redefining the term Condition to include Restrained and Incapacitated for the express purposes of ignoring them when using its Defense. People are then wondering what all this new non-standard definition of Condition might include in addition to these, completely missing the fact that it has already been 100% defined for you. It adds Restrained and Incapacitated to the normal list of conditions, for the purposes of ignoring them when using its Defense. That's all the card says, and so that's all it does. This may not be the way you or I would have chosen to write the card, but it does function just fine. There's no room for interpretation or confusion anywhere other than people trying to imagine that it says stuff that it doesn't.
Since it works just fine, I disagree that any errata is necessary. Errata might make you and I happier about the word choice, but AW doesn't tend to put out unnecessary errata just to satisfy aesthetic requests. As you point out, these aren't the only spells to be written like this either.