Have they announced that it definitely won't be? If not, it might be just a roll-out hiccup, because Argon is available to me as an agent in Xcode and I only have a Gemini Pro subscription. (Whether or not I'll ever use Argon in Xcode is a different question. I've been so impressed by Claude that I rarely even use my Codex sub. I'll be very interested to hear from others how well Argon does with Swift and SwiftUI.)