This is almost surely the way it works. I was initially thinking some kind of sensor where you put your hands but this is such a simple solution that if it's not it, the engineers are waaaaay overthinking it. I've used these before. They work and are used in all kinds of design and engineering uses so they can be reliable.I've made a few posts with a possible explanation. Basically, I think there's a simple strain gauge on the ring surface under the housing where the Joycon attaches, wired to the Joycon's rail. The joycon then supplies power to the strain gauge, and uses its own circuitry to detect changes in the strain gauge's resistance, thus making a proper bending sensor.
