Are you an artist by chance? The people who made the art are professionals, who no doubt know a lot more about scale and real architecture than you and I do, which means that everything they do is deliberate. Unless you are an artist yourself maybe you should apply for a job at their company to teach them a lesson or two? Do you really think BioWare would hire amateurs from deviant art who know nothing about art? You are at least very naive if you think so.
The scale and proportions are due to the fact that it is a high fantasy game with touches of dark fantasy here and there. High Fantasy is known to be exagerrated. If YOU don't like it, fine but don't shove your opinion down our throat and expect us to believe that your opinion is objective. Not every game needs to be realistic like the Witcher, otherwise people would get bored of the design and start to despise it like they despise the fact that every modern FPS is a copy of COD. Variety is a good thing for the industry.
EDIT: Here is a new screenshot http://assets.vg247.com/current//2014/02/dragon_age_inquisition_2.jpg
I'm actually a professional artist with experience in the industry and I agree with Johncage.
Though I'm not in the position to teach BioWare a thing or two about medieval architecture, because quite frankly, I don't know a whole lot about medieval architecture myself. And that's the entire point that I'm trying to make. Being a professional artist doesn't mean you're also a professional archaeologist or a professional architect. If I want to make realistic medieval buildings, I'd have to research medieval buildings and learn how they are made first.
How much I actually care about realism will determine how much time I would spend on research. Apparently the artists at BioWare don't care a lot about realism cause they clearly didn't really do much research on what real medieval architecture really looks like...