Sadly this video complete misses out post infectious IBS (which has real organic causes), the role of the microbiome and SIBO. There has been a lot of research on IBS in the last years and its becoming very clear that it's not a psychological condition at all.
Infections and alterations in microbiome are included in etiological causes, but they do no cause pain itself. There are only 2 established mechanisms of pain its alt in gut brain axis and hypersens. I suggest you to read latest guidelines on this topic if you are med student or doctor. And if you are a patient, which is more likely, do not read about medical conditions in non-med sources, just make an appointment with gastroenterologist. Cause like 75 % of patients tell that they want to intake antibiot and probiot to cure even multiple sclerosis, which is a complete nonsense.