> A couple weeks ago, on my linux box, an ext4 filesystem got corrupted, and some files got damaged, which involved data lost.
Which files? If some temp files go to lost+found, it is not data loss. If you had unstable power grid that caused repeated power failures while your Linux was rebooting, it would have affected only file systems that were being written at the time of failure.
> When I scanned the HDD under windows to fix errors, it removed bunch of the files stored on it.
Well. My windows claims that my usb flash devices got errors in them and demands to scan them every time. Windows was never the brightest OS on the planet. File system checks do not remove files. Neither Linux fsck nor Windows chkdsk. If power failure causes physical damage to your disk platers, readonly file system will not protect you from that. Device will be spinning in readonly mode too.
> It's not paranoia -- every filesystem, which is mounted in read-write mode, can get damaged when power disappears.
It is paranoia. File systems have journaling. In last ten years the only damage to ext3/ext4 that I've seen was not caused to power failure. It was caused temporally storage failure on hypervisor and the only impacted file systems were the ones that had stuff writing into them. And nothing of a value was lost. When data loss happened, it was caused by hardware failures and not by power. In those cases device was lost and not just file system.
You were already been told that Kodi and Libreelec do not write into your attached storage. I suspected that some media library data goes into storage device, but I don't see anything extra on my automounted disk. If they are not writing anything, your device will not have any pending writes at the time of power failure and can be safely powercycled.
Replace your USB HDD with devices that have hardware switches for readonly mode, if you don't trust OS and people.
> Who should I molest to think about implementing such feature?
You could ask udevil devs to support configuration file includes from different directory than the one storing udevil.conf. From LibreElec perspective they need writable mounts and most of users will want their storage devices mounted in writable mode to manage media files in them. So LibreElec is unlikely to change default automounter configuration for you.
Or start using iso9660 file system on your devices. That one is automounted readonly.
of videos. Moles are sleeping in January. Molasses is not. It is up, running and ready to take over Boston.