I'd agree, with the historical cadence of hardware releases, that most people would have felt the need to upgrade something every 2-4 years. And people who built Ivy-based rigs probably have upgraded a video card or storage between then and now.
But CPU/Motherboards - not all that much has changed. We have USB 3.1 (and maybe even 3.2) now, but even today's motherboards don't support that terribly well. M.2/NVMe is starting to take off, maybe. Intel is certainly pushing Optane now. But all of that can be added via PCI to older systems if you needed it.
So I don't know. I can understand the itch to just build something new. But I still don't see a strong value case to upgrade a gaming rig from anything Sandy Bridge or later just yet.
The article sounds like an excuse for Intel to push the 370 chipset - people who would be buying 8000 series CPUs wouldn't be coming from 170 or 270 chipsets yet, it's only the older systems. That isn't entirely true - a lot of people do like the option of a drop-in upgrade. The issue here is, it's not really a drop-in upgrade, it's more or less the same thing that has been available since Skylake first came out, plus two cores. Everyone is mad because they can't get those two extra cores without also getting the new motherboard and everything else that goes with it.
Shoot, a couple of years ago AMD released a 220W 8 Core CPU on legacy AM3+ socket. They didn't need to "upgrade the power delivery" for that - you could (at your own peril) drop it into the same motherboard that 4100 ran on, and run the 9590 on it without AMD requiring a new motherboard -- just because there is no reason except the charge additional money for a new chipset to do that.
Destiny has smoother gameplay - it's a shooter by people who know shooters very well. The story is much better than D1.
That being said, there's only so much of it. I don't know that I would say I've gotten my $60 worth out of it yet, and I'm mostly done playing now until a bit more content catches up. I'm by no means a content locust, I'm not in a clan, I have never done a raid or Nightfall, but I've done almost all the single player content through two different classes now, and there isn't much left except to chase Powerful Engrams and grind Public Quests.... for a very, very slow gear score progression tempo.
Warframe - a much deeper game. Tons of content out by now. It's equal parts melee and shooter. Yes, it's very grindy and lots of time gates if you don't spend real money on it, but you also have the option of ~not~ spending money on it, whereas that isn't available with D2. The grind is real, but there's a lot more variety of things to grind here that all are rewarding in some way.wd
I would lean toward the "both" camp. Your more than likely going to buy D2 eventually, and the game is fun. Warframe doesn't cost anything to play, so no reason you shouldn't be downloading it right now.