Modern Android devices have almost similar (or sightly less on low-end) specs as your laptop. And your laptop should run IDE and emulator. No reason to run comfortably.
You miss a point: an app I need to run in the emulator is extremely simple, almost "hello world"-like. The OS itself shouldn't take much resources. I would expect 99% of the CPU and 80% of the RAM to be unused when running such a humble app on a bare OS. Another point is I actually have VT-x so x86 Linux and x86 Windows can normally be emulated without much overhead but x86 Android is a different story.