I think we need to be very careful with these kinds of generalizations. I used to have severe gastrointestinal issues and I pretty much gave up eating vegetables because they irritated my gut. I attributed the problem with vegetables to fiber and I think that was correct at the time. When I finally figured out all my food sensitivities and gave my gut time to heal I was able to add vegetables back into my diet without any problem. Now i eat lots of leafy greens. There are lots of folks touting the benefits of soluble fiber to support a healthy microbiome, differentiating soluble from insoluble fiber which does not have that benefit. I don't have any grand conclusion here other than things are almost always more complicated than they might at first appear.

Jean