Yes they are. And regardless of whether they actually got the use they should have gotten, they are nevertheless very baked into the filesystem. In fact the entire kernel (or "executive" to include the parts outside of the so-called microkernel) has an ACL system for all objects, not just files. They security model is very fancy. In fact, so fancy that people can't quite comprehend it and end up doing the equivalent of chmod 777 or turning of SELinux just so they can get things to work. And don't even get started on all of the compatibility hacks MS has had to introduce over the years to deal with programs (installers and games are the big offenders) that think they can just write to files anywhere (and with hardcoded paths, no less!).Maybe these features are actually used in an enterprise environment.
The Windows permission system is so different from the Linux one, that it's very hard to make a driver that can handle those permissions. So on NTFS by default, everyone gets read/write permission, and no one execute.
By the way, NTFS does not fragment much when using Linux on it. It is not the filesystem itself that fragments, it's Windows.
I have used an NTFS partition as /home on Linux on some computer, and after a couple of months Windows' defragment tool did not show 1 red line: all white/blue.
The mentions of a "delayed metadata update model" immediately bring FreeBSD's soft updates to mind. I wonder how similar they are.
LOL @ all the clueless people here who think that somehow EXT4 has "more features" than NTFS, which happens to actually be one of the most advanced filesystems in this universe. The only issue with it is that it's proprietary.
I think at least some of those people aren't as clueless as you think, and they believe that the driver implementation ("Tuxera NTFS") may not have all of the features that "MS NTFS" has. I wouldn't find that hard to believe, though I guess it could be possible that Tuxera NTFS is a feature complete implementation.