Classic. Original. Iconic. There used to be only one Energy Drink and it was called Red Bull.
If you know anything about Energy Drink History you'll know that Red Bull is one of the OGs in the US market, unleashed in 1996, and is the catalyst that kicked off the production and distribution of every drink here after. It's the most popular single brand of energy drink on the market and has been for its entire existence.
The taste is polarizing. Immediately I taste metal which is a very weird but very distinct forward note. After this my tongue is coated in a mild apple taste, sour, close to that of a granny smith. It's not easy to drink in any stretch of the phrase but I love its taste a lot.
There were many redbull imitators in the mid-to-late 00s but most died out. Now, anything you can get off shelves doesn't come close to the flavor except the OG Red Bull. Even Red Bull's Zero Sugar type, which should come close to approximating the flavor (see Zero Sugar Versus Sugar Free) doesn't hit the mark. I think there is, now, little appetite for a sugary Red Bull imitator; any sugar-free alternative cannot come close in approximation, so nobody cares to try again. The meta has changed but Red Bull remains at the top of market, still, somehow. I don't even know many people who drink Red Bull.