If fiber cleans out your colon then would the equivalent be useful in plumbing?

No NO NO !

@Tropical_Willie Sounds like you might have first hand knowledge? Do you care to share a story about experimental plumbing degunking?

Just cleaned out the bath tub drain with a hair snake !

TW gets it right. The snake is literally the “roughage” for pipes.

No. The plumbing in your house is solid and immoveable. The only thing that pulls water and some other stuff in gravity. Your digestive system is much more complex, more flexible, more muscular. That and your house plumbing wouldn’t work in zero gravity, and your intestines do.

Good question. I did a Web search. Fiber, especially soluble fiber, does not just move through the digestive system. It is used by probiotic bacteria. Link