I have a theory that each time a new update comes out it increases the overall load on the system as more content is added. And that in turn means an increasing amount of even mid range PC’s will start to struggle with it where they possibly hadn’t before. The new London photogrammatry is a good example of that.
The fact of the matter is as the sim evolves people will need to start investing in better hardware to run it. The sim was next gen when it was released last August and I’ve got a feeling its almost always going stay one step ahead of all but the highest end hardware.