Buffalo has a large Hispanic population. The whole West side is essentially Hispanic.
Not to mention Polish, Italian, and Ukrainain in other parts of the city.
All large, very strongly Catholic populations.
If Catholicism is dying in WNY, it does not bode well for Catholicism the rest of the nation.
Things will always bode well for Catholicism because the Church was founded by Jesus Himself on the rock, Peter.
Throughout history, numbers have waxed and waned during various crises, persecutions and apostasies, as they will until the end of time.
Anyone scrutinizing numbers in Buffalo, Biloxi or Timbuktu and trying to extrapolate so as to draw conclusions on the likely future of Catholicism, is wasting their time.
There's actually a certain school of thought which says that the Church may need to shrink! How's about that!! See below.
Benedict XVI and the Church Which May Shrink. Or Not
Excerpt: At another point, in an interview published in 1997 in "Salt of the Earth" (Ignatius Press), he explained it this way: "Maybe we are facing a new and different kind of epoch in the church's history, where Christianity will again be characterized more by the mustard seed, where it will exist in small, seemingly insignificant groups that nonetheless live an intense struggle against evil and bring good into the world - that let God in."
It is a concern across the nation, but the decline in a dying rustbelt city is not the “cacary in the coal mine”. A decline in either a stable or growing city would be cause for alarm.