The threat model for AMZ is state sponsored corporate espionage, not government intruding on your and my privacy. The former cost them a ton of money unlike the later. Given their inability to enforce IP or many other laws in china even if there was similar espionage happening in the U.S. the legal system is strong enough for Amazon not to worry of losing money.
But if Amazon found evidence of code that allows for TikTok to engage in corporate espionage, why would they keep it a secret and just send out an email (and later retract) that forbids employees from using the app?
It seems way more likely that a non-tech manager at Amazon read the news and wrote the email.
The threat model of the US government, or a US company spying on a US citizen is, to the citizen, about as harmful as the Chinese government spying on them.
Actually moreso, in the case of the US government.
There is no reason for the US government to do industrial espionage on US companies. China might not be doing it either (via TikTok, at least), but it does have a motive.
but amazon doesn't care about its employees in that context, only about protecting their own company standing. (and many people will say here "why shouldn't they?!")