On X, L0vertodream also posted on X a Mac mini teardown. L0vetodream states that “it is indeed a 1-slot dual-slot with a maximum particle size of 1TB. It uses a BGA315 hard disk and the maximum upgrade capacity can be up to 2T” (translated).

However, as noted by MacRumors, it’s probably similar to their storage with only the NAND chips on board and the controller is still embedded in the SoC, tightly restricting any possible DIY upgrade or repair options.

The new Mac mini is larger than the Apple TV by a bit—5×5 inches instead of 3.66×3.66 inches—but its proportions are roughly similar. That makes its footprint significantly smaller than the old mini (and the current Studio), which was 7.75×7.75 inches. But it's also a fair bit taller: 2 inches, up from 1.4 inches.