Initialize typed arrays with non trivial types

Not sure what i’m doing wrong.
Now i get

Export type can only be built-in, a resource, a node, or an enum.

for

@export var pics := [ Pic.create("asdf"), ] as Array[Pics.Pic]

and

@export var pics : Array[Pics.Pic] = [ Pic.create("asdf"), ] as Array[Pics.Pic]

and

@export var pics : Array[Pics.Pic] = [ Pic.create("asdf"), ]

Without @export there are no errors.
I can’t seem to reproduce the old error

Trying to assign an array of type “Array” to a variable of type “Array[Pic]”

but

Export type can only be built-in, a resource, a node, or an enum.

makes it clear and i found a post which talks about this already.

Thanks for your help!