I disagree. I used to be an AIX administrator for well over a decade, got certified in basically everything related to AIX being on the side hard core FreeBSD user (still have some servers). In my opinion AIX is indeed different, but rock solid and fun to work with.
I've been since AIX v3. Moving to linux 10 years ago was like coming out of the stone ages.
But it's the same for every language. Something that's a stupid hard problem that takes a huge effort to solve is suddenly a one-liner in the next release.
