To put it another way - any potential future competitor to UNIX will have to include UNIX, via a POSIX compatibility layer. But that won't be enough, because o

To put it another way - any potential future competitor to UNIX will have to include UNIX, via a POSIX compatibility layer. But that won't be enough, because of all the extensions to POSIX. So you really need a Linux compatibility layer (which we see that FreeBSD, for example, already has). So, if you want to make a better UNIX, no matter how good your idea is - you have to implement Linux as well, in addition to all your great ideas. At that point, maybe your time would be better spent working on Linux directly.