The type system is kind of sort of vaguely ML/Haskell-like despite looking like C. Is that what you mean?

It certainly isn't a functional programming language. It's intentionally imperative.

Yes, Swift is fundamentally imperative... but it has functional concepts littered throughout in ways that are obtuse, unhelpful, and unavoidable.

This is hilariously wrong. Actual fans of functional programming would disagree with you, as there are several things Swift doesn't do to enable pure functional programming.