As you say, to start out the ratios are simple enough, but to a beginner it'd be a good exercise to plop the Red and Green science ratios into a spreadsheet for practice. Once you upgrade your assembly machines there is a modifier bonus applied across the board, now you need to account for that in your ratios. Not only can you pump out more product from the same footprint, but you potentially need to rebalance your ratios to account for the modifier.
Once you get into speed/efficiency/productivity modules complexity can really ramp up. In addition to getting the ratios correct for the machines, belt speeds need to be factored in, production rates need to be considered...
That's a bit like using crack cocaine to help learn about the pharmaceutical industry.
Satisfactory requires you to be slightly more intentional with ratios but (at least when I played) I came up with some balancing belt designs that let me get away with not needing to be super accurate with matching input/outputs. As long as I kept things at like 101% it'd all work out at the end. I'd need to do some head math to figure out initial build capacity of some product and I'd expand after that as needed.
But at least with Helmod it’s still in the game UI. Using a spreadsheet seems too much like work.
Same. I'm surprised how many people talk about spreadsheets with Factorio.
I cover a resource patch with miners, then keep building smelters until I end up with an idle one at the end of the line. When I discovered a new item I'd need to produce, I'd just built a small line of assemblers and see what my output looked like, and go back to fix any supply constraints.
Was it optimal? Almost certainly not. But I definitely enjoyed not playing it as a spreadsheet.