I totally agree for things like streams or IO like file handling or authentication. It may be fatal at the IO layer but in a GUI you want a nice error displayed

I totally agree for things like streams or IO like file handling or authentication. It may be fatal at the IO layer but in a GUI you want a nice error displayed to the user and not a crash. However in some domains you don't want to pollute your return value with a Result or Error enum, for example a BigInt library addition or a Matrix addition would be much more convenient for scientists to use if it returned a BigInt or Matrix respectively.