I received this response from SmartThings support about my Gear S3 status and SmartThings.
Thank you for your patience.
We apologize for the delayed response, we have been working on the issue that you are facing and we regret to inform you that the Samsung Gear watches are no longer able to be used in automation with the SmartThings.
We are sorry for the inconvenience caused.
Please feel free to write back to us for any further queries.
Regards,
Samsung SmartThings Support