I would not be surprised if it turned out the exact attention mechanism does not really matter, similarly to the sigmoid, ReLU, GELU movement, only the speed on calculation - and QKV is pretty good at that on the GPUs.
You need some amount of parallel compute and some amount of global comparison.
And the rest is basically a ways to parameters and scale.
(This is in theory, in practice you can get a lot of small % stability and efficiency improvements that really compound in algorithmic details of model architecture)