Well, the issue is that people will buy things like probiotics with the belief that it's helping them, and probiotics being universally healthy is one of the most dogmatic nutrition facts that anyone can recite.

If there is controversy here, then people would likely err better by not buying extra health supplements like probiotics that may be causing harm.

Same with coconut oil. I go out of my way to use it because I heard it was healthy despite it infusing everything I cook with a cheap coconut taste. If there is controversy, then I would just use other oil products.

It's not like it's a debate on which way to spool your toilet roll where inaction is inconsequential.