Confusing rules on recursive types

[ABuffSeagull]

Not sure if it's a bug or design decision, but I'm confused as to why one of these works, but the other doesn't.

Children : [Empty, Text Str, Elements (List Element)]

# (1) Doesn't work
Element : {
    tag : Str,
    attributes : List Attribute,
    children : Children,
}

# (2) Works
Element : [
    Element
        {
            tag : Str,
            attributes : List Attribute,
            children : Children,
        },
]

With the error being:

Recursion in aliases is only allowed if recursion happens behind a
tagged union, at least one variant of which is not recursive

I would imagine (1) would still work, since the recursion seems to happen behind Children, which is a tagged union.