Hokey-sounding hipster stuff. Get of my face, I'm far from being a hipster. As with all things we consume, there are going to be people who disagree or agree, and studies that prove or disprove. You found an obscure forum post, congratulations.
I'm only going from personal experience, I buy green beans and roast them, they're clean. The coffee is immensely potent compared to store bought. I get no crash, and I can drink a fair bit over what I normally drink and not get a crash or feel "sleepy". Regular coffee, the shitty feelings are almost immediate, and it honestly feels like you're getting a bad or expired drug.
This isn't really a "scare" thing, and as far as I know, people aren't out there trying to sell "mycotoxin" free coffee as some sort of scam. If there are, whatever. It has more to do with a cleaner process of harvesting and storing green beans, something "Maxwell House" or "Folgers" aren't wont to do; they just buy massive wholesale and throw that stuff in a warehouse.
I also grew up in the 80's and 90's. The news stuff you are referring to are things that no one could do research on. This isn't "advertised" or meant to "upset" people. A poster in here mentioned he gets "sleepy" while he's drinking coffee... coffee isn't supposed to do that, bad brews do that to me as well and I am willing to bet it is due to a bad batch shocking your system.
If it doesn't concern you, then don't bother. It's just information. If it comes across as "scaremongering", then that wasn't my intention.