What they have done to create this, is take their M70/80/90Q series platform, turn the motherboard upside down, add an internal PSU and create a shell with the dimensions exactly the same as the 1L chassis from the ThinkCentre series I mention above. While quite a smart move cost-wise, I think the serviceability of this PC will suffer - the RAM and M.2 SSDs are now mounted under the top cover, which is not removable, so you need to take the motherboard out to reach those.
Lenovo Xiaoxin mini PC has entered its pre-sale phase in China with a starting price tag of CNY3299, which converts to around $464. It comes with Intel 13th Gen processors, with the base variant featuring the Core i5-13420H and the top-end model packing Core i7-13700H. The other specs of this mini computer are good too.