To me, for lack of a better word, Coke has "harsher" bubbles that somehow drown out the sweetness. Which is why a can of Coke that's been open for an hour is way too sweet to me.
Hayward Kiwi (the most common commercial variety in the US) are harvested fairly hard at about 6 Brix (approximately percent dissolved solids assuming those solids are sucrose) and ripen up to about 12-14 Brix.[1]
Strawberries are usually 8-10 Brix, but a peak of the season fully ripe (and delicious) modern variety like Seascape or Tristar might be 12-14 Brix[2], the same as a fully ripe kiwifruit.
[1] https://thebenjamin.wordpress.com/2013/11/15/harvesting-kiwi...
[2] Sorry, I'm not immediately finding a good cite for this one. I've personally measured a bunch, though.
http://www.coca-colaproductfacts.com/en/coca-cola-products/c...
http://www.pepsicobeveragefacts.com/Home/Product?formula=350...
Be sure to click the 20 oz button on the Coke page (can't deep link to a particular size).