Let's apply Ockham here. Which is more likely:
1) China try a high cost, high probability of detection, low probability of success, exploit of limited applicability.
2) In a political climate of 'post truth' someone who wants to provoke a trade war with China 'leaks' propaganda. Everybody else (FBI, DNI, Apple, Amazon etc.) who ought to know about it denies that there is any veracity to it, including people who have the clout to tell the truth and damn anyone who tries to shut them up.
In the absence of verifiable evidence of this exploit, I think Ockham tends towards (2).
Yes.
I read this Bloomberg piece early this morning and it immediately raised several red flags (no pun intended).
It's reassuring to see those with more technical expertise also find it suspicious. As others have noted, the attack as described by Bloomberg would require multiple points of compromise in the supply chain and there are much easier modes of attack.
If you put in context of recent geopolitical developments, it makes much more sense that Bloomberg is wittingly or unwittingly being used as a propaganda arm for the government.
Now that the Mueller investigation is winding down and despite lots of accusations (including some meaningless indictments), no proof of Russian collusion or meaningful interference in the 2016 election has been provided. That and the fact that Putin has not been taking the bait in Syria means it will be difficult to maintain the Russian boogeyman narrative for much longer.
On the other hand
recent conflicts in the South China Sea and
VP Mike Pence's aggressive anti-China speech this morning means that there is likely a concerted effort underway to shift the focus of the populaces animus towards China.
We live in interesting and dangerous times.