The reality is that the reason software is currently the top industry/value creator when it comes to revenue is an artifact of an open ecosystem where the barriers to entry are low, and where there is space for many to experiment.

The reason software has more pay is because it scales really well. You write software once and then sell it, and your costs per copy is low. That means if you write software that increases productivity 20% that can sell for $$$$$$ while your costs are essentially fixed.