I would say they (both posts) are most likely either being intentionally misleading or they don't actually know what kind of bike they have. Looking at their the 2016 Defy 1, it seems to be disk only, and be specced with 105 level components. Even going back to 2013 which is as far back as Giant's site seems to go back, it's still speced with 105 level components. As @Criggie mentioned in the comments, 9 speed Tiagra has been discontinued well before 2016.
However, it seems that even Giant's own site doesn't have their complete past catalog anymore, but this article seems to point towards it only being available in disc brake versions.
For 2016, the world’s largest bicycle manufacturer steps forward
again, trickling down the disc brakes of the upper-tier models and
merging them with the alloy frame that takes multiple design cues from
the carbon models
It seems that by 2016, only the Sora level model, the Defy 3 (and the Defy 5 with Claris level components had rim brakes.
They are most likely not counterfeit bikes as it would be unlikely to put so much effort into a low-mid tier road bike, but it does seem they are both being represented as something they are not.