It's because Mint used to be Ubuntu without the fuss. Now Ubuntu is Ubuntu without the fuss and mint is Ubuntu with broken packages.
The funny part is that Mint was always just Ubuntu with broken packages.
Edit: I think I hurt some feelings
From Wikipedia, the free encyclopedia
Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
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