I think it’s difficult to predict what influence Hispanics will have on the Church in the U.S. I don’t mean to be unkind, but one has to first of all realize that many, many, many of them are kind of “primitive”, in the sense that their education level is often extremely low; the society from which they came is chaotic; frequently their marital lives are a mess and, often, they are virtually “unchurched”. Many came from villages where they don’t even speak Spanish, and I have met some who don’t know where the water in the faucet comes from, or whether it’s okay to drink the water from the bathroom faucet.
Some Hispanics around here have told me they have gone to, e.g., the Methodist Church because they were offered some material benefit; then to the Mormons, then to Pentecostals, and all for the same reasons. No doubt some become Protestants because they mean it. The one seeming constant is their devotion to “La Guadalupana”. Also, I have noticed a kind of “superpiety” of a heroic sort that some seem to evidence; rather like some earlier immigrant groups exhibited. It seems genuine to me. So it’s hard to know, sometimes, what direction they’re really going.
Ultimately, our parish was assigned a Mexican priest who is here on a “green card”. It was a bit of a shock to the “Anglo” parishioners, but it was undoubtedly the right thing to do. I think if I suddenly found myself in, e.g., a Japanese town, I would feel comforted being able to at least go to Mass where an English-speaking priest was the pastor. Protestants do have an advantage of a sort, in that they can manufacture Hispanic pastors or assistant pastors much more readily than the Catholilc Church can find Hispanic priests.
I have heard a lot of predictions about Hispanics (And they’re not all the same, by a long way. By my observation, they are extremely diverse; much more so than they seem to us “Anglos”.) But I don’t think anyone really knows what the outcome of the Hispanic influx is going to be on the Church in the U.S.