Those ought to stay and the literature not be bowdlerized, as a documentation of archaic usage (like the older thees and thous of Shakespearean times). At least America has no official literature and language police, unlike places like France where they are too clever by half in their insistence on plausible Frenchisms when rendering words that were invented in the English speaking world.
That's why English has the largest vocabulary and is the most expressive language in the world. We took the best words from all of them! Ban politically correct language police!