Downloading the data as a file geodatabase is definitely a feasible workflow for taking a backup of your data. We have a notebook present in our Survey123 tools GitHub repo all about working with survey data, and can be scheduled to download your survey's data as a file geodatabase periodically.
My colleague James has also created a python script that if you have an Enterprise Geodatabase can be used to copy the data from your Survey123 survey to your Enterprise Geodatabase.
Please use this link to access James' Esri Community blog on the workflow: https://community.esri.com/groups/survey123/blog/2016/12/14/migrating-data-from-the-survey-feature-s...
Additionally if you are using an Enterprise Geodatabase you can use a webhook to automatically post your new survey submissions to your Enterprise Geodatabase.