I will actually disagree with that claim. If everything was true to screen, and they didn't make the cast longer or anything, but only sync'd the cast bar and the aoe indicator with the cast bar, and when you moved out of it you were truly out of it, I think a lot more people would successfully dodge. I would even wager that many DF pugs would down Titan. Most people die to Landslide and Weight of the Land. Both have about 2 seconds cast time.. that is a long time to dodge.
Right now though, not only do you have the server not correctly noting the player's position, but the cast bar will often show up late (let's assume .3 seconds, though as latency gets higher, the time gets later), the cast bar can also seem to cut short and disappear early (we'll assume another .3 seconds). That's .6 seconds off the cast bar immediately, which is more than 1/4th the actual time you get to dodge, doesn't include the lag to player position updates, and is a large chunk of time in the heat of the moment by itself. There are also those that can dodge at 50% of the cast bar and still get hit, which shouldn't ever happen in an MMO.
Once things on the screen are true, and being out of an AOE means you're actually out, I think a lot more people will be dodging successfully. Yes, some players still won't, they have those players in every game, but based on pugs from any MMO I've played (including this one when the fight isn't Titan), I think most people will dodge. Now, Titan is probably still going to be a bit difficult because of players derping the WotL placement after the heart, but that's a different issue entirely.
I apologize if I took what you said in the wrong way, but the way it was worded read as everything in the game is dodge-able right now for everyone, and the only reason people are failing is because of skill, when that really isn't the case. Some people's indicators are so delayed that they flat out can't get out of an AOE regardless of how quickly they move, and the only way to dodge some of the skills seems to be to know when they are coming up ahead of time and move pre-emptively. That's not something people should have to do considering Yoshi himself has stated he wants the on-screen stuff to be accurate.