GOTEM! I had some sussy 3rd party kexts in /Library/Extensions/ that were interfering with the kernel cache rebuild. Looks like some ancient ZFS stuff I must've been trying to do years ago (specifically spl.kext and zfs.kext). Moved those out of that directory, re-ran the root patches, and blamo I have wifi.
Another weirdo issue I have now is that this machine refuses to show my desktop background no matter what I pick. I just get a solid gray background. Otherwise this appears to be working! Now to see if I can get my audio interface to be recognized since this iMac is my DAW...
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