The guiding principle however appears to be "Once untrustworthy, always forbidden". That is an issue.
I mean that a felony removes your right to vote, makes employment much more difficult.
You're not even using this term correctly. Not that hardly anyone is since it's become popular...but still. Whataboutism is a very specific thing, and every time someone draws a comparison it doesn't automatically become whataboutism.
However, the actual effect of bring that up is to:
1) Blunt criticism of this newly implemented Chinese policy.
2) Distract everyone from it with a debate about US policy.
No one's talking about improving the US OR China here. Because of the whataboutism, we're derailing on if the two are morally comparable or not, which suits the Chinese authoritarians just fine.