Apparently the errors found were "transcription errors" not "programming errors." Using Excel or not then is irrelevant.
Excel (and any other spreadsheet) is a nice and convenient tool to get easy tabular inputs and some results fast. Spreadsheets were one of the first useful programs on PCs.
Steps require "human transcription"? I think you've got a wrong term, and if you mistype the data you have on the paper when making a spreadsheet I don't see why you wouldn't when doing the same typing using your text editor.
"Manual intervention" would have been better. The steps involved can be copying and pasting, selecting a range (very nasty if you miss and don't notice), and even typing data from another source. Compare that to something like R where you typically load the data (even from a URL) with command like "read.table()" and most operations are implicitly over the whole data frame (no copying of data from paper required).
Excel (and any other spreadsheet) is a nice and convenient tool to get easy tabular inputs and some results fast. Spreadsheets were one of the first useful programs on PCs.