Almost all the work during the Unix Wars was wasted, entombed in proprietary forks. It's no coincidence that they were all quickly surpassed by the first kernel

Almost all the work during the Unix Wars was wasted, entombed in proprietary forks. It's no coincidence that they were all quickly surpassed by the first kernel whose license makes it mostly immune to that problem. Without the GPL, Linux would have happened just as slowly as the BSDs, and getting where we are would have taken many years (decades?) longer--and what's most appalling, most users would not be allowed to understand or improve their tools.