Unclear purpose of DefaultValue in struct types

[NinoFloris]

DefaultValue(false) seems to be fairly devoid of purpose in combination with structs.

Testing some variations for #13498 I can't help but notice it's not very usable.

module DefaultValueExamples

    type MyCommand =
        {
            Offset: int
        }

    [<Struct>]
    type RequestInfo =
        [<DefaultValue(false)>] val private value: MyCommand

        // Either want to be able to set default value fields in a struct constructor
        // 'Extraneous fields have been given values'
        new(value: MyCommand) =
            { value = value }
            
        // Or want to be able to set default value fields in a then based on constructor scoped 'this' 
        // 'Structs may only bind a 'this' parameter at member declarations'
        new(value: MyCommand) as this =
            {}
            then this.value <- value

    // Ideally RequestInfo would be condensible to this, something nice and relatively succinct. 
    // field: does not work on constructor args today, yet let or member val don't work on structs either.
    [<Struct>]
    type RequestInfo2([<field: DefaultValue(false)>]value: MyCommand) =
        member _.Value = value
        
    // Really just relevant for https://github.com/dotnet/fsharp/issues/13498 
    // This works but this then doesn't allow me to set a value for Value in any way (what's up with that, why allow it?).
    [<Struct>]
    type RequestInfo3 =
        { [<field: DefaultValue(false)>]Value: MyCommand }

    // Extraneous fields have been given values
    let test = { RequestInfo3.Value = { Offset = 1 } }

It only seems to enable the following, rather pointless, code:

module DefaultValueExamples

    type MyCommand =
        {
            Offset: int
        }

    [<Struct>]
    type RequestInfo =
        [<DefaultValue(false)>] val mutable value: MyCommand

    let test() = 
        let mutable info = RequestInfo()
        info.value <- { Offset = 1 }

Completely preventing constructors from participating in even the tiniest bit of init.

Maybe the litmus test should be: can I write my own System.Nullable (or some other more complex struct 'DU') type in F# (excluding the runtime box/unbox support for the sake of argument).