The one thing that prevents me from switching my Pixel over is the lack of support for emergency services to see your location if you call the emergency number. I know this because I called twice while having GrapheneOS installed.

I do some watersports and always take my phone with me, so letting emergency services see my location is good for my safety in case I ever got into trouble on the water. I also have a PLB, but I like to have two devices for redundancy, as is best practice.

It sounds like you're in a region not supporting E911 but rather depending on Google's proprietary Emergency Location Service. We plan to make our own implementation of what that provides:

https://github.com/GrapheneOS/os-issue-tracker/issues/1174

GrapheneOS supports E911 and has our own network location implementation you can enable which gets used by it. Unlike Google's implementation, our network location is based on location position estimation similarly to iOS. Unlike iOS, we'll be providing full offline support for it.

Counter-point: Pixel 9 with GrapheneOS, location services off, Netguard installed and active; I engage with emergency services on a regular basis for work and always receive the public record which tracks the incident. The reported coordinates are almost always within 100' of my actual location, so YMMV.

This should be higher up.