A spreadsheet is brilliant for a list. The moment two people need to update it at once, or one row needs to reference another table entirely, the cracks show up. There is no real concept of a "record" that lives in more than one view. Formulas break silently when someone inserts a column in the wrong place. Nobody quite knows which tab is the current one.
Spreadsheets aren't the villain here. They just were never built to be a shared operational system, and asking one to behave like a database is asking a bicycle to tow a trailer.