Digging through this again, it looks like the system property is probably the best we can do. The JVM implementation on AIX is weak.
1) Just use the system property to disable symlink detection. It looks like it's as good as anything else we could do.
2) We could configure the system property automatically for AIX if there's sufficient interest. It's a little difficult to tell if NOFOLLOW_LINKS is implemented but there are probably a couple of different ways we could check for AIX.
3) Use an improved JVM implementation on AIX that implements NOFOLLOW_LINKS. I don't know that one exists, but that would be the cleanest.
4) Someone on AIX could determine if "Files.readAttributes(path, BasicFileAttributes.class, LinkOption.NOFOLLOW_LINKS);" throws an exception. According to documentation, readAttributes should throw an exception like newInputStream does here. If it throws then the previous options are the only workable ones.