I have been using GrapheneOS since January, it worked perfectly, recently I needed to get some files out of the Android/data directory and thought using the USB cable would be the fastest way to do it, but it turns out that my phone is no longer capable of file transfer: choosing "File transfer" or "PTP" results in Windows saying "The last USB device you have connected has malfunctioned". USB tethering works, the same cable and USB port work for a different Android phone, I tested multiple cables that have previously worked for file transfer. I also tried disabling USB exploit protection, to no avail.
I'm on 2025062700 build right now, but I have not been using USB file transfer for at least two or three months.