The OP means, Can distro's be each other enemy?
This makes me think of Mandrake/Mageia.
I think it is rather the wish of corporations to make profits with Linux that is the enemy of a distribution. The Mandrake devs didn't like where Mandrake was going, so they started a new distro, Mageia. I wonder if all such distributions have a future.
Or I think of OpenOffice/LibreOffice, where the LibreOffice devs didn't trust Oracle and so they started their own OpenOffice version.
Or think back of Caldera, who ruined their own Linux distro.
Since the Linux developers are not into Linux for the money, I don't think that distro's are each other enemy. Canonical, for example, could see Mint as Ubuntu's enemy, I could imagine, but what could Canonical do? Nothing

I do seem to notice some "animosity" between various distro users. I wonder why, since all distro's are "related".
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