All Christians believe in an omnipotent God who could perform the miracle of transubstantiation if He willed it. That same God inspired passages from Scripture that (if taken literally) teach that the Communion meal is truly Jesus’ body and blood. That God who inspired Scripture built a Church based on the Eucharist, and that Church taught the dogma for 1,200 years before Aquinas explained it philosophically, and it remained virtually unquestioned until the sixteenth century, during the Reformation. Denial of the dogma of transubstantiation is contrary to both Sacred Scripture and Sacred Tradition.
As Thomas Aquinas wrote,
does any unbeliever profess that the changing of bread and wine into the body and blood of the Lord is impossible? Then let him consider God’s omnipotence. Admit that nature can transform one thing into another, then with greater reason should you admit that God’s almighty power, which brings into existence the whole substance of things, can work not as nature does, by changing forms in the same matter, but by changing one whole thing into another whole thing (Concerning Reasons of Faith 8).
What is perhaps an even larger problem, though, is that arguments against transubstantiation based on appearance seem to work equally well against the incarnation of the Son of God. Being made in the form of a man (Phil. 2:5-8), Jesus’ divinity could not be detected by any empirical means, and one could say his dual nature is even harder to believe than a transubstantiated Communion meal! Jesus was clearly a human being with all the limitations of humanity, yet Christianity teaches that he was also God, the second person of the Holy Trinity. These are not just big differences—without the faith as authoritatively taught by the Church since its origin, they can appear to be logically contradictory.
Hope this helps. 🙏