I think it's a mistake to talk about taste as if it were something objective out there in the world. It's something that happens *to you*, really. So to say tea is good and coffee is bad becomes suspect. It's not just tea vs. coffee, too: there's a vast range of tastes within the realm of tea and I doubt anyone likes them all.
I do think that there's something "objective" out there, though. And regarding coffee vs. tea, I think that appreciating tea uses parts of your sensory apparatus that are very different from those used in enjoying coffee. I wouldn't say one enjoyment is *incompatible* with the other but it takes a kind of mental gymnastics to shift from one to the other. Perhaps it's like enjoying spicy food vs. enjoying subtle, verging-on-bland food (not that there's no subtlety in spicy food!)
Please note: I'm not saying all tastes in the world are equal. I assume that as humans there's a similarity in the way our minds - our brains? - work such that some combinations of flavor and aroma offer us more of a chance to develop a satisfying experience than other combinations. (Exactly how this happens is a really interesting question but not one I can answer.) But when you see that lots of people you respect enjoy coffee you have to concede that the opaque brown stuff has some standing in the world.
Disclosure: I used to be a coffee lover and heavy coffee drinker. These days I desire coffee maybe once a month and try to drink it only when there's reason to think it'll be a really good cup. With all that, I'm usually (but not always) disappointed.
/Lew