Yes, my point is that it should not? Rather it should show the simpler aliases, like this:
julia> @which cross([1], [1])
cross(a::AbstractVector, b::AbstractVector)
julia> AbstractVector
AbstractVector (alias for AbstractArray{T, 1} where T)
I naively thought this simplification was done automatically, but maybe Julia simplifies only a few hard-coded cases? Then I wonder if it would be possible to auto-generate hardcoded simplification rules for all the type annotations that are used in the standard library…