Usually you use them to enable gyro, and automatically disable it when you aren't touching one of the sticks. Part of this is it lets you set the deck down without the gyro going crazy from movement, but the biggest part is it lets you "reset" your position. When using gyro aiming it's easy to get the deck turned in an uncomfortable position, and all you have to do is lift your thumbs off the stick for a moment, reposition, and go back to playing.
In comparison, when using gyro aiming on systems without capacitive sticks, you usually need a camera reset button (like Splatoon) or need to make gyro aiming only available when holding down an "aim" button (like LT).
You could also use capacitive sticks to change other controls. Some games have awkward menu controls, especially when using steam input to simulate keyboard keys. In games like this, you can have the controls normal for playing when touching the left thumbstick, but when you swap your thumb to the dpad instead it switches to "menu mode" with different binds to navigate menus easier.
You can disable wake from bluetooth in system settings now, and you can even disable it per device.
Also 180 degree USB-C connectors are really nice, but they actually aren't USB-C spec compatible and can potentially burn up or other issues. Basically when you use a USB-C cord, there's 3 way communication where the charger and cord both report to the deck what voltages and amperage amounts they support, and then the Deck decides what to charge at. The 180 degree connector isn't part of this communication, and is invisible to the rest of the system. If it's not able to support the charge rate of the other devices, it can burn up and potentially destroy your deck and cable.