I think the existence of lz4hc is evidence that what you are discussing is within the design-space of LZ4, but ZXC just did a better job of it (though lz4hc ach

I think the existence of lz4hc is evidence that what you are discussing is within the design-space of LZ4, but ZXC just did a better job of it (though lz4hc achieves better compression than ZXC)