I'm sure any route AC is rouging they have extensive data for decades on what they can charge and what their costs are. If a route is going rouge, AC has a very good idea if the market can bear it or not. Some routes like BGI and perhaps LAX they may find out they were wrong with, we'll see.

But between operating Caribbean and similar margin routes
a)unprofitably
b)reconfiguring mainline to higher density Y config
c)terminating service
or
d)going Rouge

-what was AC's choice? IMHO it's better to move these routes to Rouge where people aren't willing to pay enough extra for AC mainline over westjet or 1-stop connections rather than dragging down the entire AC brand by reconfiguring mainline aircraft to profitable configurations while keeping the AC brand. That is what the pineapples were and no one likes inconsistency (look at the 777HD reaction here when AC adapts aircraft to markets while keeping the brand name). Reconfiguring mainline aircraft with less J and going to 30" mainline seats (like US airlines...) would make nobody happy.

Not sure why you think they are indifferent staff on Rouge. Early reviews suggested the FAs didn't know how to handle Premium Rouge properly - but many recently have said service has picked up and the FAs are quite good.