> It doesn't seem to make sense why other operations on literals are optimized but these particular ones aren't optimized (much).

The existing optimizer optimizes the following cases (note that the parser does not produce negative or complex numbers, they are created by the optimizer):

   -1
   1-2j
   1/3
   16*1024
   2**32-1
   1<<12
   b'a'[0]

They all are extremely common. Virtually every Python file contain some of such expressions, and they are often used in loops. In contrary, it is difficult to find any example of using comparison operations with all constant operands.