To publish/deploy to iOS Devices you will need a Mac. That’s not an Unreal issue, that’s an Apple-imposed limitation. I am an iOS dev for a few years now, and knowing how Apple is, I doubt Unreal will make them change their mind about that.
On the other hand, Epic/Unreal could provide a (probably paid) service that would enable developers to compile iOS projects on their server and generate the archive or .IPA for those who doesn’t have access to a Mac computer. I think I’ve seen services like this somewhere, but I honestly don’t remember where.