I believe that all item active procs (that require clicking) are in fact reduced by both Time Dilation and Aldanar’s vanity and probably some others (one relic, at least). Except they don’t self-reduce.
I learned this a while ago from this informative thread by Sigatrev Pet items and devotion with time dialation.
And then there are various discussions about how the other (-)time procs work pretty much like time dilation.
Items are not affected by %cdr, though.