Comment by eloisant

They would have gotten another modern OS instead of Next as the base for MacOSX (then iOS).

Another possibility they were exploring was buying BeOS, which would have been pretty interesting because it was an OS built from scratch in the 90's without any of the cruft from the 70's.

Also, the only thing specific to Next that survived in MacOSX and iOS was ObjectiveC and the whole NextStep APIs, which honestly I don't think it a great thing. It was pretty cool in the 90's but when the iPhone was released it was already kinda obsolete. For the kernel, Linux or FreeBSD would have worked just the same.