You might think of a modern CPU as a black-box that goes out and finds (the lack of) dependencies in the instruction stream to exploit them, but this all has to be condensed into a logical circuit that is bounded in memory (registers), can be pipelined, and verified.

And even then with hardware you are typically verifying things like "The pipeline never locks up entirely" or "The cache never gives back memory from the wrong physical address" basic things like that whereas these same kinds of invariants in software are rarely profitable to try and verify.