AbstractArrayStyle{Any} versus AbstractArrayStyle{N} broadcast style

General Usage
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Suppose a package defines an array type SomeArray which, like Array, supports arbitrary dimensionality:

struct SomeArray{N} <: AbstractArray{Float32, N} end  # the element type doesn't matter here, it's merely an example

When defining the broadcasting style, how to decide whether to make it subtype AbstractArrayStyle{Any} or to make it subtype AbstractArrayStyle{N}? What’s the difference between the two options? Are there any implications for performance or safety? Is there any significance to the choice at all?

Relevant docs:

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Looking at the source, AbstractArrayStyle{N} is preferable to AbstractArrayStyle{Any} when either is an option.