Why is KOA2 soft-float while KOA3 supports hard-float?

[bozza111]

I’m trying to understand why the Kindle Oasis 2 (KOA2) appears to be limited to soft-float (armel) userland, while the Kindle Oasis 3 (KOA3) runs newer firmware that supports hard-float (armhf), even though the two devices are, as far as I can tell, essentially identical in hardware (same SoC, RAM, screen, etc., with KOA3 only adding the adjustable warm light and a slightly larger battery).

KOA2 seems to top out at firmware 5.16.2.1.1, while KOA3 can run 5.16.3+, which is where the hard-float transition appears to happen.

My questions are:

• Does anyone know why Amazon never shipped a hard-float firmware for KOA2, despite the hardware being capable?
• Is there any known way to run hard-float (armhf) apps on KOA2 (e.g. via chroot, custom userland, or other hacks)?
• Or is there any way to update or port newer firmware (5.16.3+) to KOA2, even unofficially?

Thanks

[j.p.s]

For each kindle model amazon selects an arbitrary date to stop support, then on that date stops all support, including firmware updates. The only exceptions have been updated web protocols to allow continued store access.