[llmslave2]

This is just cope. Swift's compiler doesn't choke because your logic is too ambiguous, it chokes because it's simply too slow at inferring types in certain cases, including a very common case where you write a normal Swift UI view. There is nothing ambiguous about that.

Secondly, I'm not sure why you think the mountains of boilerplate to replace | leads to semantic meaning. The type identifier itself is sufficient.

[lmm]

| is a massive footgun because it's usually exclusive in practice and occasionally silently inclusive. Having it in a language is a mistake, even if it superficially seems to make things easier, just like e.g. null.