My problem is that I had full encryption enabled on Marshmallow, upgraded to nougat and my system settings say that encryption is enabled even though I strongly suspect it isn't - my phone used to ask me for pin before booting up, but now it doesn't, so I suspect the encryption was removed while upgrading but the system settings are showing the old value for whatever reason. And I can't really wipe my entire phone just to re-enable the encryption, it's a lot of work to set up all apps again. Xperia Z5.

My point is that android encryption has problems if you can just lose the encryption between os version upgrades.