There are cases where it can be useful. One thing that comes to mind is numerical code, where your algorithms are generic over things that have *,/,+,-,==,!=, c

There are cases where it can be useful. One thing that comes to mind is numerical code, where your algorithms are generic over things that have *,/,+,-,==,!=, conversion from 0 or 1 [or some subset thereof] do the "right thing". Trying to define proper interface types for what constitutes the "right thing" is somewhat tedious without much relative gain.