After my phone updated to the latest version of iOS 26 Beta overnight, I found out this morning that I cannot get past the setup process as it fails to recognise it's connected to the WiFi and is then unable to activate Apple Intelligence.
I've tried bypassing this via iPhone mirroring on my MacBook, and while I can access the home screen that way, all native apps are inaccessible and 3rd party apps are only accessible via app switcher. The 3rd party apps (Slack, Instagram, etc) work fine, meaning the device has an internet connection.
Unless someone has another suggestion, it looks like my only option is to remove the beta software by restoring my device - although I'm going to wait until iOS 26 is fully released later today (how convenient) as I don't want to use an iOS 18 backup and lose a bunch of stuff.