Maybe I'm giving GM too much credit, but it seems to me that GM acquired the technology with the intention to bring it into their vehicles as driver assistance, not autonomous driving. They were pretty candid about not wanting to operate taxis. Cruise itself was embroiled in investigations and was prohibited from operating in SF and voluntarily ceased operations in other markets, which basically made it a target, and since GM had already dumped a few billion into it, it probably made sense to at least get unencumbered rights to the tech.