If to you "reductionism" means approach things by explaining how the stuff that makes up the thing works together to make the thing, then perhaps in some senses science is reductionist.
But I think the implication for a lot of people is that reductionism tosses out certain information and focuses only on the stuff that makes up the thing you're talking about. Feser seems to approach it this way when he writes: "If the reductive method involves ignoring the appearances of a thing and redefining the thing in terms of something other than the appearances...". That is wrong as a description of science. The former is right, and I suppose the former could be called "reductionism" in some sense, but usually people think about reductionism in terms of throwing out certain understandings of things. Appearances are not being thrown out at all. They are being voraciously pursued, compared, corroborated, and explained. Nothing about the man on the street view of color changes or is abandoned at all: it is elaborated on and expanded, not abandoned. None of the sensations or appearances are rejected or contradicted - they are housed in a broader context.