The leak is evidently incomplete since it doesn't mention confirmed elements like the Venatori but I do think there are far too many coincidences for it to be entirely fake.
Considering how many speculations and claims there have been, and how vague the claims here are, I would tell you just the opposite: throw out enough unsupported claims, and eventually one may be close to the truth. It don't imply that that particular claim is supported, though- it just means it happens to be closer than others. When you're vague enough, anything can look like a coincidence and alignment.
Which isn't to say this is a total fake: the Red Templars (or their name being dropped before their announcement) is the most relevant thing, assuming that is true. Meredith kind of broke ground on that awhile ago, and it's not exactly a secret they were going to keep using Red Lyrium. But the rest? I'd be surprised if this has as much relevance as the ME leaks did to the final cut of ME3- there were thematic similarities, but quite a bit was significantly changed from those leaks, which were far more specific than this one even claims to be.
For example, the three supporting agencies? Well, who would have thought a modern Bioware game would follow a trinary system that included angry red people, soft-power oriented blue(purple) people, and more mercenary indifferent self-interested people? It's amazing how you can make the themes fit. I'm not particularly impressed with the chosen symbols: angry red fisting for martial power isn't exactly uncommon, and was explicitly used in DA2 for a similar position. Golden Keys are also a common symbol of wealth and political power.
As for things like Lelianna being an advisor figure, Ferelden-Orlais tension, and people seeking the Golden City and fade power? We've had foreshadowing of all that.
If this had any basis in reality (and I can see reasons why someone would make a speculation reaching these things: unlikely individually but more common in the context of many claims), I'd wager this was someone glancing at a very tentative summary document more than anything concrete.