The thing about refresh rates for screens, as I understand it, is not that you need to have a 1:1 relation between your fps and hz, but you don't want to 'lose' frames due to your hz being too low. The lower both are, the more likely you are to miss frames as the image might enter the monitor exactly at a moment where it can't render it. That is why running a game @ 40fps will still be smoother on a 144hz monitor than it is on a 60hz monitor. Higher hz, just means you have a better chance at seeing all the rendered frames.
Sure 144fps sounds like a great situation for a 144hz monitor, but I think in reality it just means that you are missing a higher percentage of your frames. So you'd either need some sort of syncing technology (which AMD and NVIDIA have) or an even higher hz monitor. Again, I think, that if you don't, you will just be rendering many of your frames for nothing, as your fps and hz are not aligned. So you might as well get a GPU that renders your games at 80fps for your 144hz monitor. The difference between 144fps and 80fps in terms of money is probably a lot higher than lets say going from 40 to 80.
This is all based on my limited knowledge that I acquired from my research I did when I bought my own 144hz monitor.