I don't doubt that people have made mistakes involving spreadsheets. But these mistakes are not unique to spreadsheets. Switching to an enterprise system doesn't magically prevent data entry problems.[1] Similarly, you're as likely to implement an accounting function incorrectly in Excel as in SQL or Java.

I think that you need to show that Excel requires more data entry, or riskier data entry, or that Excel can't catch as many errors, etc. For now I'm not convinced.

[1] https://www.accountingweb.com/aa/auditing/human-errors-the-t...