Forget a magnetic mount. Instead consider a better and considerably more reliable physical mounting that securely clamps to your iPhone.
There are several "universal" Digiscoping Adapters available from various manufacturers. Speaking of personal experience, I have no hesitation in recommending Kowa's Smartoscope Vario system - designed to work with a wide range of mobile phones and optical equipment, from many manufacturers:
https://www.kowaoptic.com/Digiscoping/Smartphone-Digiscoping/Universal-Kowa/
https://www.kowaoptic.com/media/0c/19/95/1711547175/Smartoscope%20Vario%20Brochure.pdf
https://www.kowaoptic.com/media/bc/39/d7/1711547186/Smartoscope%20Vario%20Configuration.pdf
https://www.kowaoptic.com/media/0a/04/b6/1711547198/Smartoscope%20Vario%20Instructions.pdf
https://www.kowaoptic.com/Digiscoping/Smartphone-Digiscoping/Adapter-rings/
The Smartoscope Digiscoping Adapter is somewhat more expensive than some solutions, but is a solid investment. The Smartoscope solution is not device specific (unlike some) and will remain usable with your current and future mobile phone(s), these potentially being replaced much more frequently than your quality telescope or binocular optics.
You'll need the basic Smartoscope Adapter plate - and an eyepiece adapter ring that matches your spotting scope or binocular eyepiece. If you change your optics, or use multiple instruments, you only need to purchase a new eyepiece adapter ring to match - simply screwing the new eyepiece adapter ring onto the Smartoscope Adapter plate.
I have personally used this system with iPhone Pro 13, 14 and 17 - coupled to both a Leica Spotting scope and Binoculars using the appropriate eyepiece adapter.
Clearly, you not be able to use MagSafe charging when using a suitable Digiscoping Adaper. You can still use the USB-C port - this being unobstructed.
