I haven’t read the full data yet - and as with all data I suspect it depends how widespread, detailed and objective the thrust of the data collection is! - but surely if you compared like-for-like (ie a bottle of wine coming from Australia) that it would compare less favourably with a bottle of wine coming from say, The Loire? How does the wine reach the port in Australia (a vast country!), and with it’s onward journey from a port in Britain etc? And has the wider environmental impact been taken into account, say in the actual production of the wine?
I remain healthily skeptical - and I will add that these discussions, much like Brexit become mired in people ‘picking sides’ - that Carbon Neutral as an aim is just a distraction, a way-point on the terrible road of discovery unfolding before us as to just how much damage has already been done.
Surely the aim has to be to produce no carbon, not to pretend that doing something else can somehow undo the damage we’ve already done? And on that, I suspect that the ultimate answer will be that neither wine from Australia, nor The Loire is ultimately sustainable in the long run unless we drastically change the volume of carbon (and other climate-destroying chemicals and processes) that we produce in any process.