While Apple has overhauled the iMac and MacBook Pro series in the last decade, the same cannot be said for the Mac mini. Leaked schematics suggest that this could be about to change with the next model, which is also said to feature an Apple M1X SoC.
https://www.notebookcheck.net/New-Mac-mini-schematics-leak-with-a-refreshed-and-slimmer-design.554261.0.html