Wtf bro. It has four doors. It's a sedan. The A7 is actually designed like a fastback coupe. This BMW's design is the definition of sedan.
Nah, if you're talking about things being 'the very definition' of something, then both are equally wide of the mark. The 6 has 4 doors, the A7 has 5, if the 6 is a sedan, then the A7 is what used to be called a 5 door sedan - which are massively common in the UK, and predate the current 4-door coupe fad by a long way. If we start blurring the lines a little, as the manufacturers are, and start to consider the shape and roof-line of the vehicle then it's a whole other can of worms for another thread...
My point is, BMW took their coupe, stretched it a little and added two doors, Audi took their midsize saloon, stretched it a little and slapped a sloping hatch on the back... in simple terms at least. And to me, that makes the 6GC closer to being a coupe than the A7, because it's derived from a car that is a coupe. The A5 Sport Back is closer to being a coupe than the A7... (and also since the last gen A8 was replaced, probably my favourite Audi design BTW)...
FWIW, if it were my money, I'd take the 6GC over a 5 series, and probably over a 7 series, I'm sure I'm not alone in that. And this car will probably answer the question as to why the 5 series got a lot softer in its latest incarnation - this is the sportier alternative.
Either way, I'm sure neither of us will change each others opinions.... but I'm pretty sure that whilst people are still ponying up the cash for niche market vehicles, and manufacturers see their competition selling something that they are not, segments will only continue to get more blurred. Personally I welcome it, provided they can sustain it, all that it means is more choice for the consumer, and how can that be a bad thing?