| my tinfoil hat theory is that they make small features depend on new hardware. for example, let's say the new os depends on m5's exclusive thumbnail generator accelerator, and let's say it improves speed by a 20%. now, your M1 notebook than on previous OSes uses standard gpu acceleration for thumbnails will not have this specialized hardware acceleration, it will have software fallback that will be 90% slower. you won't notice it a first thought because it's stuff, fast, but it eats a bit of the processor. multiply this by 1000 features and you have a slow machine. I don't know how else to explain how an ipad pro cannot even scroll a menu without stuttering, it's insane how fast these things were on release |
The general case is hardly a "tinfoil hat theory". They openly do that, and the major reason is to tie to new hardware adoption.
That said, it doesn't usually work like you call it. It's not adding new features depending on HW optimization to slow older machines down (after all one could just not use those features in an older machine, or toggle them off).
It's rather: you want to get these shiny new features, which is all we advertise for iOS/macOS N+1, and the main new changes? The big ones will only work if you have a newer machine, even though we could trivially enable them on older machines (and some don't even need special hardware, as there are third-party hacks that unlock them and they work fine).