I gave the 2011 one away, because I couldn't upgrade it anymore, but it is still used for audio/video editing.
The 2013 one has some issues with its hard-drive and I'm planning to upgrade it to an SSD. It's still a pretty capable machine, though I would probably put Linux on it, since the macOS upgrades for that are discontinued too.
The display panels are "just" 2K in them, but still super sharp, though a bit dusty inside... They are better than most cheaper external monitors I saw ppl using for everyday work...
I think a decade of runtime for Macs is not that uncommon. 2 decades would be even better, but I wouldn't call it a "vicious upgrade cycle"...
I mean, I'm still on an iPhone Xs Max and before that I had an iPhone 7 Pro and I have no intention of upgrading, despite the back-glass being cracked on it. and not because I can't afford it, but because I won't really utilize the extra power of the latest versions.