The Eucharist is the sacrament of the body of Christ. "Body of Christ" is a metaphor whose postresurrection reference is the Church, the community of believers who corporately make the risen Christ symbolically present and active in this world between the ascension [and Jesus coming back again]
And from that quote I died a little inside.
For someone to go on about language and meaning, it pains me to see a meshing of ideas and stripping it off from their context. (In their language what I just said might sounds like: They have taken the symbolic codex of "body of Christ" and found that same symbolic representation again somewhere else but ignored the other meaningful symbols that proceed and followed on after this metaphor.)
The author makes no mention that the Eucharist is also a sacrament of the blood of Christ (the other half of the whole thing), nor do they see the Eucharist in the context of the Passover. The Last Supper happens in the Gospels and (the earliest account) is mentioned in 1 Corinthians 11:23-26. This has passover overtones, and the body (and blood) of Christ is a reference to Jesus's actual body and blood that was to be a sacrifice (kinda like a passover lamb). To say that the Eucharist is mostly about the Church is self-centered and missing the main point, as it is mostly about Jesus.
The reference to the body of Christ being the Church happens post Christ and that metaphor is even used in two different ways. Romans 12:3-7 and 1 Corinthians 12:12-27 talks about how the church is to be united and each is to help the whole. Ephesians 4:12-16 and Colossians 1:18-24 (and 2:19) make Christ the head who looks after the rest of the body. You can not mix these two metaphors too much as you really run into problems, eg. How can people's roles can be (metaphorically) an ear or an eye while also (metaphorically) Christ is the whole head?
Each metaphor expresses a different meaning. When the article said "Scripture, like Eucharist, is best understood as sacrament" I am not sure if they first understood the Eucharist (which we learn about from scripture), so I am not so sure if they have understood scripture.