A sufficiently smart linker will make that harder by removing functions that, byte for byte, are identical to one they already included in the executable ("identical code folding"; both gcc's gold linker and visual studio support that).

In my line of work I am very rarerly actully looking at a running executable with an interactive degger.

More often I am navigating through source code comparing it to logs, stack traces and other evidence that I can grab of what went wrong in production.

The source-level is important, because although I said "debugging" in my comment, what that very often comes to is first figuring out the intent of some other engineers from the thing they wrote -- and what they wrote is the source code, not the program state.