LogFAQs > #979870147

Diets sodas are basically out-of-date tech. When they went on the market they tried to get as close to the taste of sugar sodas as they could, but they were still fairly limited. Diet Coke taste distinctly different than Coca-Cola.

The ability to replicate regular soda tastes with zero calories has gotten a lot better in modern times. But as I mentioned above, Diet Coke has a distinct taste that has developed its own loyal fans. So even though Coke has made a diet Coke that taste much closer to Coca-Cola, they just can't replace Diet Coke with it. So you get an entirely new line of diet sodas with the Zero label instead.

There is also an added benefit in marketability. Diet sodas were heavily marketed to women back in the day, so much so that they picked up a stigma of being an effeminate drink that still persists even after marketing went more gender neutral. The Zero line gave a more masculine diet soda option with none of the diet baggage. Heck Pepsi arguably leaned in too hard with diet soda for dudes with Pepsi Max, which later got rebranded as Pepsi Zero Sugar when that became the favored industry term.