I think they Y axis (async/sync) should be auto-scheduling/manual-scheduling.

That would clarify it for me personally, because I couldn’t understand that axis.

In that sense - why do we want manual scheduling? Predictability?

Missing from that diagram: cycle-accurate MCU/DSP, realtime-threads (Linux), realtime-threads-if-you-ask-nicely (MacOS), RTOS, GPU.