This guy seems like he's fairly plugged into the fan community. He could honestly be just some guy reading WDWmagic and sharing his opinions. Funny.
Well he seems to be making a big deal out of nothing. This would be like Disney complaining that
Disneyland didn't grow as fast as DCA when it was being upgraded and Cars Land opened. It's just common sense of sorts. I will say there's a possibility that things don't turn out for him...
1) DAK may not surpass Epcot. Avatar should have a positive effect, and the other park enhancements are awesome. However, it's conceivable (and the author's handling of this is crap) that Frozen could considerably grow Epcot attendance. Frozen as much as he'd love it to be the case, isn't over. In many ways it's just getting started. This is another reason that I think he's a Disney fan. He takes an almost illogical swipe at Frozen. A Maelstrom fan perhaps? Frozen 2 could also be out by 2020 further reigniting interest in the attraction.
2) New attractions at Epcot could be launched. I think Shanghai has something to do with further investment. I'd imagine that since they already have multiple buildings already to go, they could install new attractions in like two years. Much less than say the construction of a full land.
Though I actually found myself agreeing with
@Yellowstonetim a fair amount. It's a well known fact Epcot has the highest per capita spending, guests stay longer at Epcot than the other two laggards, and that the financial health of Epcot is secure. One has to be the bottom, and if it's at the bottom because one of their other parks is successful what's the big deal?
Of course it could do more to host large groups of people. I think that's where the biggest criticism could be. Epcot needs to do its part to alleviate the attendance problems at MK, but it's not a rush with the other two moving to address it.
Ironically for all the complaints about Epcot's state, it wouldn't surprise me if it was as profitable or even more profitable than either of the Universal Parks.
Alcohol and food sales in a international themed environment with fireworks= $