This isn't some spaghetti ERP on Excel or some other blatant overuse of the application. This is tagging some lines on a CSV file to categorize expenses. A few filters, a few formulas, create a summary sheet with SUMIFS or just create a pivot table, done.
Evaluating the problem tells you how complex the solution needs to be. This problem of categorizing basic financial transactions is pretty basic and I'd take the basic approach every time.
Well in this particular case - yeah, excel 100% of the time.
But I think the point here was exploring different paradigms and their trade-offs. I appreciate that a lot, as I think we're stuck in various local optima as an industry - and spreadsheets seem to be one of them (once they pass a certain complexity threshold).
I'm not sold on the "everything in clojure" model here, I think you could accomplish all this does with a script written in $LANG and a little DuckDB (and probably a half dozen other similarly suitable approaches), but again - I appreciate the goal of exploring the solution space, especially when it's using approaches that I'm not that familiar with.
Evaluating the problem tells you how complex the solution needs to be. This problem of categorizing basic financial transactions is pretty basic and I'd take the basic approach every time.