Submarine Pipe Dream?, page-27

The French subs were also superior to Chinese subs. The Chinese are not happy with AUKUS because the doctrine changed from defence of Australia's home waters (what the French subs are for) to offense where Australian forces serve as an auxiliary for US navy in Taiwan Strait specifically targeting China.

Only nuclear subs can reach Taiwan Strait undetected (based on current technology). May well not be true after 20 years.