does apple one include iTunes Match

It does not include Match. I never said that. What I said was Apple One includes Apple Music which in turn has a feature that works the same as Match. It's a bit like saying you can buy a hamburger patty or you can buy a hamburger (which inherently includes both the patty and a bun). ;-) All Match did was sync your purchases and private sound tracks to iCloud for your personal use. Apple Music does that too but also includes access to Apple's entire online music collection on a borrowing basis.

Apple used to have a comparison page but it is really hard to find out about Match these days unless you know it exists. For a comparison instead see: http://www.imore.com/apple-music-vs-itunes-match-whats-difference

For just Apple Music Apple Music - Apple

For Match Subscribe to iTunes Match - Apple Support

I can't speak for Apple Support but since Match is a relic feature and Apple has been trying to get people to use Apple Music instead, somebody hasn't blown the dust off the archives. ;-)

Try this:

If you want to cancel a subscription from Apple - Apple Support

Apple One includes Apple Music which in turn includes Match. I'm surprised Apple still keeps Match going, though I am sure that for some it is all they need and want (and I am all in favor of that).

Is there any documentation from Apple that substantiates this? Apple support tells me that Apple one does NOT include iTunes Match.