Cats Can't Taste Sweetness, Study Finds
npr.org
npr.org
It's not even clear whether two humans are experiencing the same flavor or taste when they agree that a food is "sweet"
OK but that's like criticizing every science result by saying "how did they control for the possibility that I'm a vat brain and nothing they did was real"
but that's kind of straw-manning the point I am raising, I think.
There are just certain specific things or questions that maybe science isn't really equipped to answer properly, and things related to one's actual experience seem to constitute a broad category for which that seems true, thus far.
So, no, it's not the same as disbelieving any random scientific study by questioning whether the universe itself is real or whatever. It's really just saying that, in a real universe we all share, science has its limits as to the proper scope of its inquiries and explanatory powers.
Why would they need to taste sweet? That's something their prey does.
They eat herbs too. Maybe that's related.