Try maintaining code from the 1960s. (Score 1)

The summary thinks code for PIIs is old. HA! My employer is still running programs where the base was written in the late 1960s. IBM mainframe assembler code. It has had dozens of developers with differing styles (and skill levels) working on it over the decades. It's still being patched when there's no way around it, but it's no surprise that result of all those years is unmaintainable. IS management is afraid of replacing it due to how fragile it is and they think it works although I find issues with the results it generates on a fairly regular basis. How much sense does that make?