Even aside from maritime operations, we do need an attack helicopter capability.
Should we have Attack Helicopters... probably.
Does it have anything to do with embarked aviation... nope. AH is the wrong tool for the job, even armed recce. The days of flying around the ocean looking for ships visually are long gone. Maritime armed recce should be done with a light MH, such as a Lynx, or perferably a Wildcat.
I couldn't find a picture, but VU-32 used to operate CH-135 Twin Hueys from ashore for fleet general support. If we could afford a split fleet (and granted, we may have to if DND wants to embark on the AOPS) then maybe bring that back with a Canadian built UH-1Y. Although I'd perfer a Wildcat, it's a pretty big ask.
If we were to switch to the SH-60, I think a split fleet of Romeos and Sierras with increased numbers makes a lot of sense.
Getting back to the topic at hand, I think the CDC without manned embarked aviation is short sighted. This alone, in my mind, should be enough to split fleet and have a smaller helicopter.
I will admit my bias, as I spend my time researching how and why the decisions that led to the Sea King on the St Laurants were made.However, we did operate a 10 ton Sea King from a 2,250 ton DDH for a long time, quite effectively it turns out.