If you want to get the best of both worlds - contact trace and keep it off your phone it's technically possible. You don't need any deep technical knowledge but you will need to accept some inconvenience...
You can sign up for a SMS forwarding service at Twilio. That way you get a number and you can configure it to forward SMSs to your actual number. It will cost you monthly but hey, so does punting. You can also probably just ask their support team to configure the forwarding for you.
Now, when you scan the QR code, use WeChat and it will open a WeChat browser. Fill in your details but put in the Twilio number. You'll get a confirmation SMS and the QR scan will work. If someone gets covid then the twilio number will get contacted and you can figure out what you want to do from that point onwards.
I'm not sure if you use your real number on the web form if it will link to your app or not.
Anyway, that follows the spirit of contact tracing and keeps it off your service NSW app. Let's stop complaining and get on with our lives
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