The blocky spreadsheets of yesteryear could run in a few kilobytes of RAM. Today, that's microcontroller territory. From there, I can contrive a few answers:

- A spreadsheet that runs in a RISC-V+Core-V device is less susceptible to supply-chain issues and geopolitical stresses.

- Price. The hardware needed to run a text-only spreadsheet is worth about 10 bucks or less.

- Energy consumption. Now the server with your business data can run deep within energy-starved communist Cuba...probably.

- Better security. Plenty of people and armies get nervous about keeping tallies of dangerous toys in computers with lots of ICs and closed-source blobs made in enemy territory. Just enumerating all those ICs and blobs in a conventional laptop or tablet is difficult.

- Size. A smaller, cooler chip is easier to hide, which matters if you spent your trip to the motherland working on something you don't want customs to find out. In that case, you can use your laptop as a terminal to the sensitive data in your server running inside a button of your jacket...