linux-6.11.4.arch1-1 has a Bluetooth issue, bypassed with kernel downgrade
Using Gnome, my Bluetooth mouse wasn't connecting anymore. Found some comments on Reddit saying downgrading the kernel solved the issue, it also worked for me.
I usually keep a second kernel (LTS or my own manually built package) around in case of driver regressions like this. Occasionally you'll see issues in the firmware package as well, Intel WiFi in particular seems to experience more regressions than you'd expect. If you want to help get things like this fixed faster collect log data and file bug reports before you downgrade so they can filter upstream to the driver maintainers.