Bottlenecking calculators are a bit of a joke. Because every task is different. Some games are more CPU heavy, others more GPU heavy. People play at different settings. You might run into memory limits first.
I have one game where my current config has a 6% GPU bottleneck according to those calculators. And yet the game I would need to upgrade for is heavily CPU limited, so much that my GPU clocks down and is still only at 30% usage.
How can a GPU running at 30% utilization at half it's clock "bottleneck" a CPU that is running at 95% on all cores?
I have another game where my GPU is indeed the limiting factor, but only if I disable my 200 fps cap, because it can't do more than 230 fps in that game, while my CPU could sufficiently feed a stronger GPU at much higher framerates.
In both cases, the "GPU bottleneck" is irrelevant.