Well, the specific concern is that all new tech ships with OTA update capability. Infrastructure should probably never have this in the first place for a variety of reasons, but it does and it will because the of huge cost savings it can enable. When the Chinese government can tightly control the companies under it, and those companies control the OTA update, then nothing produced by those companies can ever be considered safe so longer as China is considered adversarial. The same could absolutely be said about US made products being used in countries that the USA is adversarial against, and that's likely how the USA government started thinking about it.
"Hey, what's a great way to deal with China if we go to war? Whataminute, they could do that to US!"
Just look at the havoc that has happened unintentionally due to bad updates being pushed out on a large scale and extrapolate to what could happen with a malicious actor at full control.
"Hey, what's a great way to deal with China if we go to war? Whataminute, they could do that to US!"
Just look at the havoc that has happened unintentionally due to bad updates being pushed out on a large scale and extrapolate to what could happen with a malicious actor at full control.