Computing SHA hashes is embarrassingly parallel, but LINPACK is NOT embarrassingly parallel. LINPACK, like many scientific applications, requires a fair amount of communication. Comparing hashes per second to LINPACK scores is really apples to oranges. A better comparison is to simply add up numbers of similar GPUs and CPUs and ignore all the benchmarks.

Bitcoin enthusiasts should also consider that the Top500 is not an exhaustive list; governments have much more computational power than is on the list.