My two cents on the topic is that HSR from Melbourne to Sydney should implemented as a series of incremental upgrades, rather than a single megaproject.
It wasn't done as single megaproject. Instead, it was done in small segments. A bypass around a town. A section of road between two town upgraded to dual carriageway. Eventually, over 40 years, the whole road was upgraded.
We should be doing the same thing with the train line from Melbourne to Sydney.
Hey @RM_Transit not sure if you're aware but nsw trainlink who run the syd-Melb xpt have placed an order to replace the xpts and it doesn't include sleeper carriages. I think that would've been worth including in your vid because it really kicks the can on expanding sleeper service another 30 years down the road. It's not insurmountable, but it's difficult to see expanding sleeper service as a viable way fwd when we have brand new carriages that don't have that function.
I think a bit of advocacy and awareness around that issue would be helpful!