Murch actually expands on that a little more in the interview. He doesn't mean the specific activity is what your job should be, it's more like "the basic similar activity."

So for him, as a video editor, it was using a tape recorder to record sounds, and reorganize them in an aesthetically appealing way. He didn't actually get into video editing specifically until after college IIRC.

I first touched a computer after completing my university degree and I still remember the happiness I felt by simply running a DOS command and seeing the expected output.

It does't matter when the plug finds the socket - it is always electric.