I also have the same problem. I have installed a MacOS Ventura on an external SSD to preserve my internal SSD lifespan, and I cannot install a single app which relies on Kernel Extensions, for instance, pCloud, Tuxera, DriveDx, and so forth. Is there any solution available? Is this problem under Apple radar?

It looks like something is missing. Maybe is an oversight from Apple. It looks like when we try to load an extension the com.apple.kernelcaches/kernelcache under PreBoot is not populated or not created. I've purchased an external SSD in an USB-C enclosure. I have two Mac Mini m1. One at home, another at my work. I wish I could turn off my office computer, unplug my ssd in home computer and boot my whole environment to keep working, and vice-versa. I wish Apple correct this. That would make M1 machines perfect.