Saving Flux models

Checking documentation for current stable Flux v0.13.16, I am wondering why it is suggested so many transformations (struct, functor) prior to saving a model with Flux.state(transformed_model).

In which sense just saving Flux.state(model) is not preferred?

Preferred saving method follows here for reference:

julia> using Flux

julia> struct MyModel

julia> Flux.@functor MyModel

julia> MyModel() = MyModel(Chain(Dense(10, 5, relu), Dense(5, 2)));

julia> model = MyModel()
MyModel(Chain(Dense(10 => 5, relu), Dense(5 => 2)))

julia> model_state = Flux.state(model);

julia> using JLD2

julia> jldsave("mymodel.jld2"; model_state)