One of my really old tablet still running KK, it's the last version that doesn't make the tab run like dogshit
29+12=41, perfectly ordered
Galaxy S5 still have (IP67 iirc) water resistance with removable battery
Updates are for techminded folks like us, average people hate updates.
The best way to use idm would be some kind of "trial reset". It used to work great, but when I made my own money I purchased it so I don't know about the state, could still be working now
The best bet for you is finding a rom that pass safetynet by default (los doesn't), and consider using kernelsu. It's still in early stage and maybe dangerous, but if you are knowledgeable enough it's a saving grace.
Wonder why they don't add, most phones now have no jack, gotta differentiate