If you check the according thread, you’ll see that it were not just low-end PC owners who complained about performance, it even included RTX3090 owners.
And it was not only reported as a bug&issue thread, but it got voted and discussed a lot, so I’d say this category was appropriate.
So I’d say it was a very broad issue and it indeed was fixed with SU5 (at the expense of visuals for users that used ultra preset already before, which I did too).
Now let them see what they can add back via options to get more flexibility for high end systems - hopefully without introducing the intermittent fps loss that many of us were suffering from, despite higher end systems that were underutilized.
EDIT: Here are some exemplary separate threads people opened with high end hardware. It’s easier to find them than reading the big performance thread: