Rolling releases for issues with newer hardware and the AUR. That’s really all there is to it. There are plenty of ways to be “unique”, but at the the of the day, nobody else is ever really going to care.
If I bought myself a 6 year old Thinkpad, I’d put Mint over Arch on it in a heartbeat. For the desktop that’s constantly upgrading, it gets Arch because it has the fastest releases and biggest community to troubleshoot stuff.
Honestly, it never got big enough for that to even matter. It just lost the content war to the PS2 Xbox and GameCube. Shenmue, Jet Set Radio and Sonic Adventure aren’t exactly enough great exclusives to justify buying the non-Halo machine or the console built by the company that “won” the previous generation.