Yes, that is quite true Meg. I would say the major slippage (deference to false science combined with historical criticism applied to Sacred Scripture) came about in the 19th Century. Hoping that Cassini the expert on these matters can jump in here.
I appreciate your charitable response. I do hope that Cassini will jump in too, and give his view of it.
It does seem like, as you say, that the slippage came about in the 19th century (or thereabouts), but I don't really know a lot about it. Certainly the view of a flat earth slipped away even before that.
Modern science became a replacement of religion (of sorts) at some point in the past; but now, of course, many people take modern science as a fact, and as a way to explain the world, and they leave behind a Catholic cosmology, though it would seem that the Church was not completely clear in what the exact cosmology is.
NASA is just so much more glamorous and impressive, with all of it's CG'd photos and such. Science fiction movies and books from the last century have also played their part in dismissing a proper Catholic conception of the universe, though of course we would not be in agreement of what the earth and heavens are shaped as. What we can agree on, maybe, is that modern science has corrupted the fact of a God-centered and created universe.