My big problem with Linux is not that it was based on UNIX although in all honestly I would probably have adopted it to some extent if it had been based on VMS or any other DEC OS. UNIX was never my idea of an OS done right. My real concern though is that OS development has become, with the exception of Microsoft, little more than tweaking Linux. One can do this because the source is available.
Having the source available is not completely bad as it can be very educational to read and play with source code. It’s a good tool for education. But it seems to me that it has made developers, in a sense, lazy. There is little to no incentive to start from scratch or the make major changes when most short term goals can be reached by tweaking Linux.
It used to be that companies had an incentive to create new and better operating systems. They needed them to make their hardware useful. Now that they can just tweak Linux there is no real incentive to do more. Also since one can’t easily make money off improvements to Linux AND one has to share what one developed with everyone there is no incentive to differentiate your hw/sw combination at the operating system level.
Apple moved to a UNIX core some years ago. Based on FreeBSD I believe. Why? Well it was too much work to continue to develop their own OS from scratch. And software was not their core strength either – though they have had some really good coders there from time to time. Apple is more a hardware company and using free OS code was a natural for them. It was cheap and easy. Not always an indication of best or innovative.
And then there is the mono culture risk that so many people are concerned about. It concerns me as well but the answer is not to replace a Microsoft mono culture with a Linux mono culture. I’d live to see three or more major OSes “in the wild.”