It's not exactly a joke, but it's certainly vastly easier than before. We had a couple runs at him pre-2.0 on my server by bringing some guilds together. Even though we got him down sub-30% a few times, it wasn't enough to convince everyone to return the next week to make forward progress (inter-guild coordination is a beast). I'm disappointed that we didn't clear him before the patch, since the kill means a lot less now.
Regarding the achievements, btw, I don't believe there is any difference in the achievement system between a pre-2.0 kill of DT and a post-2.0 kill. One of the guilds on my server did it post-2.0 (hadn't done it pre) and received the same achievements and titles that they would have received pre-2.0.
For me anything that is easier is a joke...Also the difference with DT 10 stack kill and achievements I was referring to has to do with the timestamp. If you did it pre 2.0 your timestamp/date was from the first moment you logged on when 2.0 launched. In my case it was about 30 mins after servers came back up for early access. I havent heard of anyone rushing to do DT 10 stack in that first week so the timestamp is a good indicator to see who did it before 2.0 hit.