The marketing and trademark is more important than the formula. If you created and sold a perfect Coke clone you wouldn't make a dent in their market share. You could make one better than Coke and not make a dent because it wouldn't be Coke.

I would bet that supermarket brand cola would sell more than it does now if it were closer to Coke.

I think sooner or later, everyone who drinks a lot of soda will try the store brand as well as other colas that are non-belligerents in the cola wars. Some of them are ok, some are good for some mixed drinks, some are so bad I won't even finish the pack. Even though I prefer Pepsi, if I knew brand X was pretty close to Coke, I might choose it when it costs less and money is tight.

I think his idea was to make a very close copy that costs very little compared to the finished product, to e.g. save cost of your own consumption (in the video it says he made a mixture that can be mixed with water and sugar to create 5000 liters of Coca-Cola)...