I've seen a lot of cold "draft" coffee appearing that is infused or pressurized with nitrogen gas (as with Guinness beer). The added nitrogen leads to a "smooth, creamy" mouthfeel. (Although it seems to dissipate very quickly – over a matter of minutes.)
I've never seen carbonated draft or bottled coffee – i.e., coffee infused or pressurized with carbon dioxide. Dissolved carbon dioxide occurs naturally in sparkling spring water and fermentation, and is the gas added to most "sparkling" beverages. Is there a reason cold "sparkling coffee" is not an item?