I think the claim isn't that "language has no rules" but rather that the "rules" are far more context dependent and subject to change over time than would ordin

I think the claim isn't that "language has no rules" but rather that the "rules" are far more context dependent and subject to change over time than would ordinarily be implied by the use of the word "rules". Even at the lowest level of phonemes to morphemes, accents introduce a huge amount of variety, and it doesn't really get more orderly as you increase the level of abstraction.