It was society-wakening at the time. He employed aspects of yellow journalism to draw attention to the dark spots, to expose the mess lying underneath the fading formica surface on American public life and society.
He had to engage. He had to annoy and disgust and enrage. It all started around the time of Nixon's dirty tricks campaign and they bludgeoned politics into the festering pit of corruption and back-hand deals it is now. That game they played didn't slow down. People like Roger Stone doubled down each time they had a chance, and they got rich off of doing so to the great detriment of much of the US. There was no stopping. The "good" people in politics didn't play the same way, and they continually got buried by drama and scandal.
You see, he couldn't just report on it. He had to make it real. The problem was, with time the issues became decentralized and more common. That's when he began to lose heart. This is why by the end of his life he had no laser-like focus any longer.
I understand where you're coming from, but he shouldn't be conflated with the type of the self-indulgent writing you get from the likes of Vice. Those guys just often grew up worshipping this guy because it wasn't "boring" newspaper reporting, and they all want to be him. It's nothing like the same.
There are still takeaway lessons, though. The whole gonzo thing got journalists more interested in the field and long-term investigating on a personal level. I've seen some great docs that occur in first person in really interesting and sometimes life-threatening scenes because of the influence of HST.
edit: grammar