If you want iMessage you still need an always-on Mac, whether that's the main moltbot gateway, or the MacOS app running in 'node mode' to allow a moltbot gateway to use it to send/receive iMessages.
I noticed when I was reading Federico Viticci's post about it that he was using telegram, which has much better support for "markdown"-y rendering, which looks a lot nicer than iMessage. And then I thought to myself, why would iMessage actually matter? The only other use-case would be interacting with texts, but almost anyone can tell when someone is using an LLM to text - I feel like our texting styles are so personal, and what is there even to gain from using an LLM just with text messages? So is it even worth it to run on a Mac?
I think you need to register on a real Mac (2 of 3 of my MBPs use OCLP), but then can use an emulated one if you add it to your Apple account. Either way, I don't recommend to use a protocol behind such a moat. Probably better to use Signal or Threema.
I expect someone will eventually get around to reverse engineering the various M series specific instructions for qemu. Does imessage make use of hardware attestation to register with the remote endpoint?