systemd? More like systemK! But seriously, are non-systemd systems not vulnerable to the FUSE portion of this? (CVE-2021-33910)
My "systemK" joke was indeed implying what you said, that systemd is "a key place in the stack where you would need to be super careful." (Almost Kernel-like.)
And my question was legitimate, although poorly-researched. Answering myself: CVE-2021-33910 only affects systemd, not all FUSE in general.