Are kernel side software recommendations on-topic?

From a user perspective a kernel-side software isn't as different as userland ones (on windows, you launch .sys instead of .exe).

But it appears questions about finding a particular filesystem or choosing utilities for forcing to delete files or choosing the best scheduler related to a specific configuration got closed as not related to software recommendations. On some OS those kind of questions use userland programs (they still use privileged CPU ring).

So are questions about programs which run at kernel-side/privileged CPU ring on-topic on SR?