Its hard to explain. It was a soft drink that wanted to taste like Pepsi, but just couldn't quite do it. Pepsi minus the after taste would be another way to explain it. I don't know it just didn't taste right to me.
Yes, Crystal Pepsi had an odd, blandness that's not easy to explain. Sorta like drinking decaf coffee instead of regular. It was a great idea, a soft drink without artificial colorings, but half the flavor profile was taken away too. I didn't expect a caffeine-free cola to be flavor-free as well.
I tried drinking regular Pepsi recently and it tastes horrible so I can only imagine how bad Crystal Pepsi tasted. The Pepsi of today tastes nothing like the Pepsi that I grew up with in the 90s and even occasionally tried in the 2000s. However, there's Pepsi Throwback that uses real sugar instead of high fructose corn syrup. I always pick it up a case whenever I see it at the local WalMart. Pepsi Throwback really brings me back.
You expected it to taste citrus-ish like Sprite or 7-Up but then your brain would wig out as it tasted nothing like you were expecting. I never thought it tasted exactly like Pepsi, but it was sweet in a way similar to it.
I personally enjoyed the Jedi Mind Trick it always pulled on me and was sad to see it go.
Edit: I wouldn't say it was vomit inducing. But would expect ANY soda that has been sitting for 20+ years would warrant the same reaction.
"When magic is explained, it is no longer magic." -Haggar the Witch, Voltron