1. Everyone chooses for himself what systems to use it. No one is forcing you to use LE.
2. The launch system in Coreelec is not compatible with LibreELECE and Armbian. If you run coreelec on your TV box, you will no longer be able to run LE and Armbian normally until the full recovery of the standard firmware via the USB Burn Tool and the new activation of the universal multi-boot, which is used in all new systems.
Test images LibreELEC KODI-18 Leia for platform Amlogic S9xxx
To start the system from external media, you must use a universal multi-boot. This variant of multi-loading system is fully compatible with Armbian etc systems for TV boxes. If it is already activated with the previous images, you do not need to repeat the activation.
Test variants of Libreelec KODI-18 (Leia) images for s812.