Systems Software vs. Application Development is a more appropriate categorization. There's a tier that sits in the middle who write "platform" software on top

Systems Software vs. Application Development is a more appropriate categorization. There's a tier that sits in the middle who write "platform" software on top of "systems" but for "applications", but you could argue that those people are much closer to app devs than system software devs so they may as well be lumped in with them. There is simply less supply of systems jobs and they have a higher talent requirement, so it's pretty rational for people to be content to stay at the application dev layer. Where is the evidence that systems devs get paid more? My impression is that lots of systems development historically has been unpaid or paid via open source foundations. And the route to getting paid doing that kind of work seems a lot more bumpy and less straight forward, almost like a "starving artist" kind of life story. Whereas app dev is pretty simple. You go to college, you crank on LeetCode for a couple of weeks and then you get a 6 figure salary working on JIRA tickets. It's a brainless, hard to get wrong life script.