first it was a 767 second I always question that report because the Chinese sent it to the USA for out fitting in the first place. I mean they could probably have done it in china or paid the Russians who do it for Putin's command post one. I mean its like they were offering it up. And then they never followed it up. They claimed the bugs sent the bird back to service for air china and then never tried again to do the same on there own. Seems more likely they realized that they could just do what they ended up doing using air china 747s for cheaper well scoring cheap propaganda points
The problem is the US never outright rebuked that accusation. And usually China seldom make random accusation especially against another countries unless provoked first.
There is also another case of Australian intelligent try to bug China embassy in Australia and was caught red handed. That accusation was also never denied by Australia. In fact, they try to tuck it under table and not to talk about it.