You're using "progress" as a judgement of something that's "better" or "improved" ... like "technological progress".
A "language progress" is a movement in usage and meaning. We "progressed" from "thy" "thee" to "your" "you" etc. It doesn't mean the words starting with "y" are "better" or "clearer" (in fact, they are the opposite of the previous formal/informal distinctions.) Nevertheless, language/culture has moved on.