Immerse yourself in a workplace setting where Excel is the first thing that people grab for anything but text editing. You'll see how insanely productive people are. Now actually try switching to LO Calc.

I've done this several times during my career, to see if LO Calc would ever come up to the performance of Excel. To be fair, I haven't done so since I switched to Python.

Here's the experiment I would conduct. Generate a column of 5000 numbers. Now graph them. Now make a few token changes to the graph such as modifying some of the aesthetic parameters. The difference in processing time was profound, last time I tried it. Also, there was a noticeable "latency" between clicking something, and seeing something happen, that made it quite un-ergonomic if not physically painful to use. I'm sensitive to this because I get eyestrain headaches easily.