I believe the core issue here is that iOS has pretty strict Bluetooth HID (Human Interface Device) profile support, and a lot of inexpensive or generic VR controllers only connect as "presentation remotes" or "media buttons," not as full MFi (Made for iPhone) game controllers. That’s why they often behave like a basic mouse or only let you swipe or click—not enough for real gaming input.
iOS 18 still relies on the MFi framework or now, more commonly, full support for standard Bluetooth game controllers like Xbox Series X/S, PS5 DualSense, and select certified third-party options. These controllers are fully recognized by iOS and will give you full joystick + button support for apps that actually support controllers. However, here’s the catch: most of the current “mobile VR” apps on iOS don’t support game controllers at all. They’re designed for head movement and limited tap interaction (especially since Apple now focuses on Vision Pro for immersive experiences).