Question

when people read writings from the early days of america it becomes clear that the english language...

Answer 1

were based in the Early modern English. A system moderately similar to the present day English, with a few notable differences in pronunciation.  Early American writers were concentrated on describing and trying to make sense of their challenging new environment and unfamiliar people. Using letters, diaries, and reports as a way of communication.

Answer 2

The English language has greatly evolved. English during the early days of America was more formal and there were grammatical differences.