LOL, I'm with you, I wouldn't be half as annoyed with him if he didn't use that silly speak. I live about a half hour from him - no, people don't really speak like that in New England.
Anyway, as to a 5th park, I'm sure there are those people sleeping in bed right now who just got some sort of invisible chill knowing that something would be here in the morning to sink their claws into, and we'd get the classic "OMG are you stupid? A 5th park won't happen because..." folks who will trot out the same arguments against it that we all know.
That said, I'm not of an opinion either way (could be one, could not be one), BUT...in this case, I think this is a classic case of 'Hill throws some crap on a wall, hopes some sticks.'
Why For?
Well, first of all, it's been over a dozen years since the last Disney park opened in Orlando. In the first three decades they built four - and by 2021, that will be over 20 years since AK opened. So, the chances of them not building a new park in Orlando in over 20 years is a bet one could hedge rather well. So it's not a crazy notion, especially since the length between the last park (AK) and 2021 is almost the time frame between when they built all four existing parks.
It's perfect fodder for his "throw some crap on a wall" style, as no one will be able to prove him wrong for a decade, and my guess is by then he thinks he'll be the King of All Media, since he has seemingly abandoned his website to do the sparse stuff on Huffington (my, how the Huff Post has gone down down down the drain since it was sold - I still can't figure out how they have credited Hill-billy as an "award winning writer" LOL). There he can get away with more fluff and BS because his audience aren't the Disney experts most people who come through these parts are.
So, if in 10 years they do build one (not a crazy notion, again), he was right, and if he isn't correct, he probably figures he'll be elsewhere than he is now and won't care. Or, my personal prediction - that he'll still be doing the same crap now 10 years from now, and if they don't build a new park he'll say, "Well I really meant..." or "...it turned in to..." some new put put mini golf or something or other and he'll say, "See, another gate!"
In short, could be true. May not be true. While Hill-billie had a few interesting tales early on (most of which remained unfinished, some many, many years later), there is rarely any good info out of him that either isn't posted elsewhere (namely, here) or that couldn't be put together from various postings and conjecture (again, mainly from here).
While many of us feel it needs work (i.e. Lucasland), MGM is now pretty unarguably a full-day park, and with Avatar over at AK, it sounds like in five years AK may be as well. So it's not impossible to think that they are thinking of a 5th gate - Iger might actually have realized (unlike many fanboys) that maybe the reason AK didn't draw higher attendance to the overall resort is because of the theme and implementation. Wonder how many people saw AK ads on TV and were like, "Yeah, we've got a zoo here at home..." in spite of the NAHTAZOO marketing.
The more I think about it, it almost sounds logical - Disney saw what UO did with one land, imagine if Disney did something on that level in a whole park. It's almost too unreal to think about, when we've spent this century in video-screen/meet'n'greet style development at WDW, but it is a tantalizing thought nonetheless.