This portion is fairly similar to the 1975 GIRM. Many vessels for Communion are made of substances other than precious metals. My sense is that many Catholics perceive that other metals, glass, crystal, or ceramics avoid the appearance of being ostentacious. I’d say that judgment depends on the community, but a person would be hard pressed to prove it’s necessarily a sign of a lack of reverence.
327. Among the requisites for the celebration of Mass, the sacred vessels are held in special honor, and among these especially the chalice and paten, in which the bread and wine are offered and consecrated and from which they are consumed.
328. Sacred vessels should be made from precious metal. If they are made from metal that rusts or from a metal less precious than gold, they should generally be gilded on the inside.
329. In the Dioceses of the United States of America, sacred vessels may also be made from other solid materials which in the common estimation in each region are considered precious or noble, for example, ebony or other harder woods, provided that such materials are suitable for sacred use. In this case, preference is always to be given to materials that do not easily break or deteriorate. This applies to all vessels that are intended to hold the hosts, such as the paten, the ciborium, the pyx, the monstrance, and others of this kind.
330. As regards chalices and other vessels that are intended to serve as receptacles for the Blood of the Lord, they are to have a bowl of material that does not absorb liquids. The base, on the other hand, may be made of other solid and worthy materials.
331. For the Consecration of hosts, a large paten may fittingly be used, on which is placed the bread both for the Priest and the Deacon and also for the other ministers and for the faithful.