It's not meant for calculations. People do all sorts of calculations in Excel. This is for when you have a bunch of rows with text in them, say for example customer testimonials, and you want to summarize and/or determine sentiment for each one so you can analyze it without reading it all.
I saw a demo of it, and if it works as advertised it could be cool. You can use the results from other queries in other cells, so it feels like using Excel, just with text instead of numbers.
I personally don't have any use for it, but it has a lot more potential to be useful than most of the AI garbage I see.