Fairphone have recently released a version of their Android-15-based stock OS (FP5.VT2E.C.059.20250908; release notes) which claims to fix the inability to boot with a broken fingerprint sensor (with a couple of public reports seeming to confirm that it does fix that issue).
(Still dunno what the story is for whether /e/OS would be affected and if so when it will get the fix, despite asking; holding off Android 15 until I know.)