The spokeswoman contends that Xiaomi is not owned, controlled or affiliated with the Chinese Army and is not a 'Communist Chinese Military Company' as defined by the NDAA [National Defense Authorization Act]. Xiaomi claims that she is now evaluating the possible implications of the classification of the DoD prior to taking action.
Although the Biden administration may have reversed the order before then, it's important to see an electronics firm like Xiaomi on the list. Many of the other firms on the list are more industrially focused, dealing in transportation, aerospace, shipbuilding, plastics, telecommunications, manufacturing and other types of infrastructure.
Huawei, the world's number two phonemaker, is also on the list, but Huawei also develops large-scale telecommunications equipment; US lawmakers have been especially concerned that Huawei is part of the nation's cellular infrastructure.
This registry is not the same as the "entity list" of the US Commerce Department, by the way, which usually keeps US companies from exporting technologies to blacklisted companies, such as the DJI dronemaker. But several Chinese firms including Huawei (and Chinese chipmaker SMIC) are also on both lists.
Speaking of the Commerce Department, it is going forward to attempt to stop six nations, currently designated as foreign adversaries, from supplying communications facilities to the United States, including China, Russia, Iran, North Korea, Cuba, and the Government of Venezuela, Nicolás Maduro.