I've similarly observed massive improvements doing it daily, but in general people tend to have very strong opinions one way or the other which makes me think it's very dependant on the teeth's in-between distance, microbiome, brushing technique and more.

Some people can just like brush once a day with a regular toothbrush and have perfect teeth, meanwhile some of us have to do scientific experiments, use sonic toothbrushes, floss, and use mouthwash or our teeth start falling apart immediately lol.