Yes, your understanding is correct. Smecta and Changyanning did not change gastrointestinal peristalsis, Smecta said it would not change, and Changyanning was used for gastrointestinal damp-heat accumulation, so obviously neither of them was used for diarrhea caused by cold.

Generally speaking, western medicine takes effect faster than traditional Chinese medicine and has many side effects. As a traditional Chinese medicine, Kangbain Changyanning overcomes this point and takes effect faster than ordinary Chinese medicine. On the other hand, Smecta overcame the side effects. Apart from the temporary side effect of constipation, there are almost no other persistent side effects because its ingredients are not absorbed.

Believe my answer is the most direct and clear.