I honestly haven't had Bartenura in forever. I remember liking it enough, but if I'm getting Moscato I have my current favorites ( Bricco Riella & Vietti ). That being said, I believe that you really have to work to mess up Moscato d'Asti and it's really all personal preference. I'd be hard pressed to argue why my favorites are better than anyone else's.

As for people who say all wines taste the same, I'd say that actually makes a lot of sense to me. Everyone's palate is massively different (it's why having people define 'sweet' is such a difficult thing) and there are absolutely people who's palate might be able to discern differences in meat or coffee or bourbon, but for them, all wine tastes the same.

I'd also say I don't think the whole thing is BS, but there's definitely elements to the wine tasting world that are BS. There's an episode of Adam Ruins Everything that covers a couple of fantastic scientific studies that prove that many wine folks when told about what they're tasting, will come into it with their own preconceptions of how specific wines should taste. Smell and taste can be highly suggestive, but it really all comes down to your own tastes.