The French deal was for converting their nuclear subs to diesel electric with most (90%) of the work to be done in Australia and was won against good bids from Germany and Japan. The Oz mission then was to go near Indonesia for intelligence gathering including counter terrorism and people smuggling. The Oz mission has now changed to counter China especially as they are building super carriers and their own nuclear subs. At the same time the French deal was blowing out in total cost and the proportion to be done in Oz dropped (I think to 50%) on last negotiations.
We now have F35's that can network with the USAF. We have AEGIS Hobart class destroyers that network with the USN. So it makes sense for our subs to network with the USN. Not sure how the British can help but they have had the one sinking of a cruiser by a nuclear sub. That sent the entire Argentine navy back to port. The French need to " passer à autre chose "