Not very long, to be honest. Maybe a month, and I'm not using them like I was when I was playing BotW or Mario Odyssey. In fact, I still use my Pro to play Rocket League because I trust it more. I really love the concept of the joycons, the same as I did with the Wii/nunchuck. It's a bummer that since day one we've had this problematic aspect of the design.
After reading your earlier post I tried this. The joycon is still drifting but it's way less noticeable and its useable now. Hopefully it says like this.