Could you please elaborate on this? Is there any direct confirmation of this? There wasn't any single answer from anyone affiliated with the Swift core team on this specific point. Or from any lawyer for that matter.
Also, "using Swift" isn't in the claims ¯\_(ツ)_/¯
When drafting the claims writer (patent attorney or agent usually) will add clauses to work around prior art. You can't just add unrelated features though, the features need to have synergy to represent a single invention.
[I've read a lot on USA patents but only worked directly with UK and EU patents.
This is not legal advice.]