Sequoia unlock with Apple Watch issue

There's an issue on Sequoia which affects unlock with Apple Watch on at least T1 models (possibly others) since at least macOS 15.4 (possibly earlier). Confirmed by multiple reports, but unknown scope and cause currently, as the main T1 dev @covasedu lacks an Apple Watch.

Discussed in this thread.

Lots of unknowns at this time, only opening an issue to document the problem publicly outside of Discord.