I concur. And I have some insight into this. I wrote a command line invoicing tool[1] which I referenced on an earlier thread since I knew a bit about generating PDFs and thought that was the "hard part" of this.

The real value is in being able to respond quickly to queries like "What were the invoices numbers for client X in Jan, Feb 2022?" when your accountant asks them. Managing that, timesheets etc. in a way that can give you insight into business financials is what's really useful once you cross a (low) volume of invoices.

That being said, the output of the tool is extremely good looking.

References:

1: https://github.com/hamon-in/invoice