I haven’t thought about it in a while but the premise of the article rings true. Desktops are overall disposable. Gpu generations are only really significant with new cpu generations. CPUs are the same with real performance needed a new chipset and motherboard. At that point you are replacing the whole system.
Is there a platform that challenges that trend?
This has been true for a long time, CPU sockets don’t last long enough to make upgrades worth it, unless you are constantly upgrading. Whenever i’ve built a “futureproof” desktop with a mid-high end GPU, by the time I hit performance problems I needed a new motherboard to fit the new CPU anyway. Only really upgradable components are storage and ram, but you can do that in your laptop too.
The main advantage of Desktops is still that you get much more performance for your money and can decide where it goes if you build it yourself.