Coming out of BigCo consulting, pretty much every decision in our sales and solutioning pipeline had Excel somewhere beneath it, simply because it was the fastest way to do financial and project modeling for rapidly-changing requirements.
In general, I found that most clients have both "god spreadsheets" that seem to continually accrue data and control operations in often opaque ways, and nightmarishly-complex reporting spreadsheets generated by upstream systems that, if one thing goes wrong, explode into bits of #VALUE!s. It's neither good nor bad, just a fact of life. One client we engaged with -- one of the largest companies in the world -- had what we called "the ten-billion-dollar spreadsheet," because that's literally the amount of annual funds it controlled, even though it was completely invisible at the executive level. (Sad to say, but my lasting contribution to humanity is probably helping unlock an additional billion dollars of capitalist investment a year by moving a key part of that spreadsheet to a simple but far more accurate regression model.)
In general, I found that most clients have both "god spreadsheets" that seem to continually accrue data and control operations in often opaque ways, and nightmarishly-complex reporting spreadsheets generated by upstream systems that, if one thing goes wrong, explode into bits of #VALUE!s. It's neither good nor bad, just a fact of life. One client we engaged with -- one of the largest companies in the world -- had what we called "the ten-billion-dollar spreadsheet," because that's literally the amount of annual funds it controlled, even though it was completely invisible at the executive level. (Sad to say, but my lasting contribution to humanity is probably helping unlock an additional billion dollars of capitalist investment a year by moving a key part of that spreadsheet to a simple but far more accurate regression model.)