Joycon drift, and all other thumbstick drift, is already a solved problem.
- Use bushings that actually have some abrasive resistance and aren't softer than a fingernail.
- Use a non-contact based sensor to determine the XY position of the stick. Hall effect, optical, strain gauge, whatever, we've had the tech for 50 years.
The reason why they haven't done this is one very simple reason: $$$