Sure, of course there aren't 1000 sailors +++ marines and aircrew, thats why this whole thing is a "what if" even if it was a Canberra class or a Banana class (and I doubt the heads on a Canberra class can handle 1000 Diggers for much more than a week).
The point being, if the "political will" was ever present to do something like that in Canada, is a limited LHA/LPD ship of limited capability the way to go, or a hybrid aircraft carrier "like" the the America class* the better theoretical option (again, considering that no such ship, whatever size, is ever going to be an actual option for Little Canada).
To be clear, I'm not in favour of any type of ship like this for the RCN (ever), but I don't see the point of considering half arsed little ships pretending to be in a league in which they are out-classed from the start, regardless of what oceanographic region that we pivot towards.
I think the Japanese are seeing that problem with their new concepts of potentially operating the F35B off the Izumo class and considering that at a "mere" 27,000 tons it is too small for the growing purposes for which they apparently now have the political will attributed to them: "....The government and the LDP envision deploying refitted Izumo carriers with F-35Bs to the southwest, where they could respond quickly to problems in such areas as the Senkaku Islands, which are administered by Japan and claimed by China as the Diaoyu,” ...
Similarly, somehow I don't see South Korea being content with its new Dokdo LPD once they start flying operations.**
Anyway, just a thought experiment, wondering if political will/ (modest needs + modest means) = 20,000 tons of "showing up" or 45,000 tons of "being there."
Also, with Australia, Korea, Japan, India and the US operating many types of LHA, LPD, and half of the USN CVN's in the Pacific, why do we need to pivot that way at all?? Our economic interests are already militarily covered by others.
* https://thediplomat.com/2014/04/does-the-us-navy-have-10-or-19-aircraft-carriers/
** https://archive.is/fuJZP