What is the use for atime? In the early days, it was used for homebrew HSM systems, where files that were very rarely read were good candidates for deleting or moving to other storage. Today, HSM is either not done any more (because disk capacities are large enough that storage management no longer matters), or it is done correctly inside file systems that have built-in and more intelligent HSM functions.
So in my opinion, on regular Unix systems, atime can always be turned off.
