I wonder why is it not default in the first place. It avoids nagging issues with locked snapshots and does what most users would naively expect (I remember that most people need some time to understand locked snapshot problem in the first place).
Does this option have any negative impact?
Great question. Agreed...on most installs, I turn on this vol option just to not have locking issues.. haven't heard of any performance issues, but might be an issue when they go to delete a snap. What other options do you modify? I have a script I go through and change a lot of options and defaults these days...and typically enable clone_dependency, vol lang C.UTF-8 language, enable unicode and convert unicode (new install...not to an existing volume not enabled which can be a nightmare for performance), then change several of the small default tcp window sizes... I also started mirroring root on every new install too similar to clustered ontap where we mirror vsroot local and to all other nodes as long as there is space and a different aggr to mirror to.