Right answer, wrong reason. The reason the bans went on Australia in the first place is because President Trump scored a big win over China in their trade war in 2019 with the signing of their trade agreement, forcing China to pivot significant chunks of their imports away from current suppliers - that includes Australia - and sourcing them instead from the United States.
The bluster around 'diplomatic issues' was only the result of China wanting to save face for being so soundly beaten in the trade stoush. It also allowed China to give Australia a few freebie slapdowns for several things that ruffled Chinese feathers but weren't important enough to them to have done anything about them otherwise.
If the Morrison Government were smarter, I'd have strongly considered the possibility that they deliberately antagonised China to provide cover for our masters in Washington who basically pushed us (and several of our industries) aside to get a piece of the Chinese action as part of their trade victory. Some of their instruments of choice were awfully blunt, almost like they wanted to be tagged as the reason. And, at the time, the US was talking a lot of anti-China talk so it served the dual imperative of softening up the Australian public for a set against China.
