I was explaining this to my daughter in quite simplified terms the other day- we evolved to taste sugar and enjoy it because finding a sweet edible plant meant we had a source of energy to help us hunt that day. Pretty useful if you're a hunter-gatherer.
So we seek out sugar. Now we can get it whenever we want it, in much more massive quantities than we are supposed to be processing. Most of us are addicted. I'm not an exception.
Fruits healthfulness is commonly exaggerated. Consuming the fiber in whole fruit along with the sugar is better than just straight sugar, but it's still something that should be moderated. Most fruits have way more sugar than fiber as well. Also that really only applies to whole uncooked fruit, using heat and mashing up fruit removes pretty much any of the benefit from the fiber.
When you juice it, the natural sugar has the same effect as added sugar.
It's only better when it's locked in with the fruit solids because then it's a slow release rather than a fast sugar shock to your system, which can fuck with your insulin tolerance because that also needs to spike for your body to do anything with all that sugar.