It's a miniature computer starting at $599. We can safely assume LLMs wasn't a chief concern when Apple designed this computer. It comes with an integrated 155 Watt PSU (45 Watt is reserved for the three Thunderbolt 5 ports).Too bad they didn't have a M4 max version of Mac mini (probably too much heat for such small size), and the 64GB limit is also not really good enough for very large LLM. 273GB/s memory bandwidth is also not high enough. A 128 GB M4 Max (with double memory bandwidth) in a slightly larger case would be very nice for running a large LLM. Could even steal some business from NVIDIA I'd say.
Have some reasonable expectations and grounded perspective