This whole thing is generally seen as pretty funny domestically. The biggest fallout so far was the ABC getting caught doing dodgy editing. Then we had to put up with Karl Stefanoic twerking on the morning news. Criticizing the dances is seen has misogynistic, which of course in the current times people want to avoid. Its getting a lot of international attention now, as a generic funny news story.
That said, the author advocates 6 diesel Attack class SSGs followed by 6 SSN's. If we were to go the nuclear route, this strikes me (a layman) as possibly a more reasonable path to get there in that it would buy us time to establish the needed support base. Will leave the finer details to the pros...
While possible, its not as easy as it seems.
Building and operating and decommissioning nuclear submarines is a time consuming and expensive business. AFAIK only one Navy globally actually has a proper decommissioning system for nuclear submarines. The UK hasn't even completely recycled any of its nuclear submarines, and Russia is an example of what not to do. If we want to build capability quickly, conventionals are the way forward. While China is building nuclear submarines, their nuclear program has been dramatically less successful than their conventional program.
What is the aim anyway? 20kt transits? Attack class looks to be approximately as fast on its transits as Barracuda. Being submerged for a few weeks is no longer a problem for conventionals either and underwater endurance is increasing at an extremely high rate. While in defence you want the best gear, you can also win by making the other side spend too much, on units that are too expensive, to slow to produce and take too long to develop.
While the Attack is similar to the Barracuda, its not the same. Going nuclear would basically be another class again. However, both France and Brazil are working on reactors for Barracuda type subs. France has put a lot of effort into making nuclear power more sustainable and affordable, not based of nuclear weapon fuel lines, and using low cost LEU. That would be more attractive.