Unexpected Output from `DeepMutable<any>`: Bug or Feature?

I would have expected

DeepMutable<any>

DeepMutable<any>

to produce

any

any

, but it produces a very complex union type instead (https://effect.website/play#1b31ab42321e). Is it fair to consider this a bug?

Unexpected Output from `DeepMutable<any>`: Bug or Feature? - Effect Community