Skip to timestamp 5:55 to go to the fix and the explanation without the fluff
Saw a thread on Reddit that's gaining a lot of popularity on a potential fix to the Joycons
The concept of the problem is that over time, the metal plate holding the bottom of the Joycon gets bowed overtime by force from the spring and pressing it, which eventually causes the readings on the pads to be imprecise. If anyone has any Joycons that haven't been fixed to try the pressure method of seeing if it fixes it(doesn't require disassembly) to see if its actually the housing that could be causing it.
If this actually works for the masses, I'm surprised a multi million dollar company couldn't find the reason why it happened.