Since you're the one bringing this this time up I'll throw this out there: fiber is the source of as many problems as solutions. The idea that high fiber diets are appropriate for everyone is not supported by the science, and there are tons of places where reducing fiber is tremendously beneficial. Look into the FODMAP diet, for one obvious example.
https://www.nadialabs.com/pages/how-to-use-the-toilet-correc...
It takes me less time to pass a number 2, than to go number 1. It is not loose, but it is soft and just ... blooop, done. When it's like modeling clay - not getting enough fiber! :-D