Yeah true. At level 35 and up I've seen less, "wait for the tank to aggro then go" (though there is admittedly WAY LESS of than on HC than on Live for obvious reasons LOL). At that point folks got their nukes and have gotten some end management, and it's teams rushing from spawn to spawn. Less waiting for the tank, less waiting for lockdown from the dom/controller, less waiting for debuffing from the defender, corrupter, etc.
Hell in most AV fights, some one just yells "I found the AV" and fight.
I suspect . . . thought that this started long before HC. I think the exact time when AT roles became less and less important was the issue they made it possible to switch sides, followed by the additional change to be able to make ANY AT on ANY side. After that role became less important when you have multiple ATs on either side that can fill a role. (Some, multiple roles at the same time LOL).
Now the question is . . . is that a bad thing. I'm . . . not really sure. I'd argue with the history of COH and it's anti-trinity history, PROBABLY not.
Interesting side discussion.