The PREEMPT_RT patchset (sometimes confusingly referred to as RT-Linux) is slated to improve the kernel quite a bit wrt. "low-latency" and "responsive" workloads.

I'm not sure why this is such a problem in Linux, where latency is really not such a big problem in Darwin/MacOS/iOS.

Architected for throughput instead of latency.

> Speaking as an OS engineer who's worked on both kernels a lot, Windows is way better under the hood for low-latency, responsive end user stuff than linux

Still it's probably a lot cheaper to fix some latency issues on linux that to maintain your whole kernel. The main issue with linux is the GPL for drivers, a long with kernel API instability.

> The main issue with linux is the GPL for drivers

That's the main benefit with Linux. OEM drivers on MS Windows are a shit show, even on Windows 10.

I don't believe you: https://en.wikipedia.org/wiki/SCHED_DEADLINE

One costs a lot to maintain, another doesn't.